Your system needs to be able to show hands of normal opening bid strength, and to preempt when your side is weak but distributional. Opposite a very strong opening like a Standard American 2, the emphasis is almost entirely on preemption. The stronger their opening is, the less you need worry about constructive methods for finding games for your side.
There are two main reasons defending against a forcing opening is different than a nonforcing opening. First, if you pass, you are guaranteed a second chance to act. If you have a hand likely to be able to extract a penalty, you don't need to warn the opponents of your strength immediately; you can wait until they finally make a nonforcing bid, and enter the auction for the first time by doubling their final contract. Likewise if you are unsure whether or not you want to enter the bidding, you might find it convenient to wait and see on the second round whether you wish to compete.
Non-jump overcalls of forcing bids need to be used with care, to avoid helping the opponents! If RHO forces and you pass, LHO must bid; if you act, LHO has additional options: he may now (re)double, or pass, or make a sufficient bid. For example, over a Precision 1 opening, you actually give the opponents more bidding space if you double or bid 1, and break even when you bid 1; only bids of 1 and above consume any of their bidding space.
This means that, whenever possible, our lowest-level actions against a forcing bid will be aimed at making it easy for our partners to act, perhaps by jumping, at their first turn to call. For a low-level overcall to be right, it either needs to convey a message to partner so urgent that it is worth giving up the extra bidding space, or it needs to lead to a cooperative preempt.Top of page Exit this page
You need a way to show each of the 4 suits, normal- or preemptive-strength. You don't need a way to immediately show a strong hand. With a strong balanced or 1-suited hand, pass the first time, then bid notrump or name your suit (or double for penalty!) later. The bidding will probably still be low on the second round while they try to have a constructive auction. You may, however, wish to be able to show weakish two- or three-suited hands immediately.
As mentioned in the general comments above, the first 2 or 3 steps over a forcing opening do not take bidding space away from the opponents. I like to use these steps to show 2-suited hands (4-4 is fine at the 1-level; wait for 5-4 at the 2-level) since partner is likely to be able to raise one or the other of my suits.
Aside from the first few steps, all suit bids are natural, all jumps are preemptive. Against very strong bids, very aggressive preemption is good, especially when your side is not vulnerable. You need almost never worry about your side making game.
If you have a favourite method to show 2-suited overcalls over 1NT, consider using the same method over a strong club (leaving out the step to show a 1-suited or strong balanced hand). For instance, if you play Brozel (2 = clubs and hearts, 2 = diamonds and hearts, 2 = hearts and spades, 2 = spades and a minor) over 1NT, use the same four meanings for Double, 1, 1, and 1 over a Precision 1, and for Double, 2, 2, and 2 over a Standard American 2.
If you don't already have a favourite 2-suited method, or your 1NT method doesn't adapt well to strong clubs, here is my personal favourite, called "Chasm", an acronym for "Colour, Shape, Majors":
|Over 1NT||Over Precision/Blue Team 1||Over Strong 2|
|Double||Either & or &, 5-4 or better||Double||Either & or &, often 4-4||Double||Either & or &, 5-4 or better|
|2||Either & or &, 5-4 or better||1||Either & or &, often 4-4||2||Either & or &, 5-4 or better|
|2||Both majors, 5-4 or better||1||Both majors, often 4-4, nonforcing!||2||Both majors, 5-4 or better, nonforcing!|
|2||Natural, 6-card suit||(Optionally, use 1 (2) the same as 1 (2) and don't reveal weak hands with both majors)|
|2||Natural, 6-card suit||1||Natural, maybe a good 4-card suit, primarily lead-directing||2||Natural, similar to weak two opening|
|1NT||Minors, may be 4-4|
|Natural; good 5 or bad 6-card suit vulnerable, may be as bad as KJ8xx if not vulnerable|
|2NT||Minors, at least 5-5||2NT||Minors, at least 5-5||2NT||Minors, 5-5 (may risk 5-4 if not vulnerable)|
|3NT||Gambling (solid minor)|
As mentioned above, with a hand too strong for a simple overcall, or with a strong balanced hand, pass initially.
If you prefer simple defenses, you can just play all your suit overcalls as natural and lead-directional, like 1 above. NT bids should still be for the minors. Bear in mind the caution against doubling or bidding 1 without a compelling reason, as otherwise you are helping your opponents.
In "two-way club" systems such as Polish Club, the 1 opening, while forcing, does not promise 16+/19+/21+ points like a strong artificial club opening -- it may also be a 12-14 notrump hand or a real club suit.
Against such systems, there is less need to preempt (and more danger of your side still owning the hand). Your jumps to the 2- or 3-level shouldn't be as wild as vs. Precision; normal weak jump overcalls work well. You might even decide to treat a Polish 1 almost like a Standard club: double for the majors, 1NT for the minors, all suit bids natural. But it's more important than ever to pass on the first round with the strong balanced hand because of the increased possibility of being able to double opener's weak rebid for penalty.
You could use the same defence against Roman or Neapolitan 2D (4-4-4-1 or 5-4-4-0 distribution, 16 to 20 or more HCP) as you do against a strong club. You can't be as agressive on coming in with poor hands since they will know opener's distribution and be able to punish you more often.
Many people, however, are unwilling to give up 3 bids to show two-suiters over such a high-level opening. Additionally, it is a little bit more dangerous to double without diamonds, because you give them the extra bidding room to discover a diamond fit; this is discussed in more detail in the section on weak forcing bids without a known suit like Wilkosz 2. The simplest defence against Roman -- double shows diamonds, 2/2/3 show sound overcalls, 3 and higher are preempts, 2NT Unusual -- is probably the most common.
Roman 2 and "Mini-Roman 2" show the same 3-suited distribution but more limited strength -- most commonly, 11-15 HCP. Again, it is possible to use the same defence as against a strong club. But it is more common to either play natural bids, the methods from the weak forcing openings section, or a modification of the "Flannery defense" below.
There is no set rule for exactly where "strong" ends and "weak" begins -- indeed you could even have a third defence for in-between-strength conventions. My suggestion is to use just two strength categories, but discuss in advance with your partner what rule you use to distinguish the two categories. If you are worried about a misunderstanding, take a few seconds at the start of the round to look at your opponents' convention card; if you need to ask "Partner, what do we play over their 10-13 2?" go ahead. This sort of question is perfectly normal before you pick up your cards to play (and grossly improper after the auction begins.)
Lastly, beware of treating limited bids like Mini-Roman as strictly forcing. Some partnerships allow responder to pass the "forcing" opening when he has a weak hand and a long diamond suit of his own.Top of page Exit this page
Great news! Over these bids, your side has all the the advantages! Since they have promised possession of a suit, you have a cuebid available -- often a cheap cuebid. And you still have the option of passing the first time because you're guaranteed a second chance to bid. In fact, if you have such opening bids in your own bidding system, you might want to consider changing them -- because these bids will hardly give your opponents any trouble at all.
The only such bid in common use today is Flannery, a 2 opening promising 4 spades, 5 or more hearts, and 11-15 HCP. Also, old-fashioned strong two-bids, though not exotic conventions, fall in this category. (In the 1960s the Italians experimented with systems in which 1 and 1 were natural and forcing, but often on 4-card suits, perhaps with five of some other suit. But very few of the modern experimental systems play their artificial but limited openings as forcing -- see below.)
If opener promises 5 or more of a suit, your side can safely forget about ever playing with opener's suit as trump. Over an opening that promises only four cards, opener's suit is still a possible, but unlikely, trump suit for your side.
My recommendations in general terms:
Passing initially with a strong one- or two-suited hand is more dangerous than over a forcing opening with no known suit, because there is a possibility that responder will be able to jump raise and shut you out.
If their nonforcing bid promises 5 or more cards in the bid suit, you can treat it the same way as you would a natural opening bid, just with some additional information about opener's hand. The most common convention in this category is Flannery 2. Like Flannery 2, this bid shows 5 hearts, 4 spades, and minimum opening strength. Hearts isn't a playable suit; since opener has only 4 spades, it's still conceivable you might want to play spades, especially since you will know exactly how they break if you declare. Here is the full list of responses:
You may also see a variant of the Mini-Roman 2 in which the 2 bidder's singleton is never diamonds, allowing responder to pass 2 with tolerance for diamonds. Here, since opener likely has only 4 diamonds, you may want to still play in diamonds.
Against this convention, I find double = equivalent of a strong notrump, 2NT = unusual, 3D = natural, works fine.
The traditional Precision 2 is "almost forcing" like Mini-Roman 2, but with a catch: opener's short suit is always diamonds. This opening is used only with 4-4-1-4 or 4-4-0-5 shape (or 4-3-1-5 / 3-4-1-5 with a weak club suit.) Over this, 2 and 2 should be natural, since opener has only 4 (sometimes 3) in the majors. You can choose whether to use Double to show a diamond suit or to show a strong notrump hand. Whichever you pick, you will wish you had a cheap bid to show the other one -- Murphy's Law in action.
The only bid in this category which you are likely to meet is the catchall Precision 1 opening, which in some styles of Precision promises no length at all in diamonds, merely denies a 5-card major or 6-card club suit. For the Precision 1, treating it as a natural 1 bid (but remaining alert for opportunities to bid diamonds naturally on the second round after a sequence like 1-Pass-1-Pass-1NT) is good enough, though perhaps not optimal.
As a matter of bridge logic, nonforcing bids that don't promise specific suits aren't playable except at the very lowest levels of bidding, especially with a strong hand: it is silly to waste the bidding space which you need to sort out what suits you have.
In some countries you may encounter artificial openings at the one-level. For instance, TOSR, the Transfer-Oriented Symmetric Relay system, uses 1 to show 9-14 HCP and 4+ hearts, and 1 to show 9-14 HCP and 4+ spades. If responder is too weak to look for a better contract he may bail out by passing instead of completing the transfer or bidding his own suit. Most competitions that allow such systems require the people playing unusual methods to make their system notes and suggested defences available in advance. One simple method is Double = semibalanced 11-14 or 19+, inviting partner to pass for penalty; 1NT = 15-18; a bid of the suit opener promises = a takeout double of a standard opening in that suit, other new suit bids = natural. See the section on defending Wilkosz 2 in the defense to weak openings page for more on handling this type of "I have opener's artificially-bid suit" double.