Game tries typically happen after 1♥ 2♥ auctions or 1♠ 2♠. It is a way of inviting partner to game, by describing assets or features of the hand - so partner is in a better position to know whether the hands complement each other or not.
Before we start - are game tries a good idea?
The expert bridge world is not in agreement over this, there are two schools of thought
1. Just bash game, don't give information away to the opponents (that may help with their lead and defence). So, you either bid game or you don't, no invites.
It may sound strange to some people, but there are very prominent world class players who take this approach, and it certainly has its merits. It puts pressure on the defence, they have less information, and with less information mistakes are more common - "keep the defence in the dark".
It is worth noting that this approach is not used with slam bidding which needs to be much more scientific - bashing game is considered to be okay, bashing slam is typically not what we do.
2. Game try - There are also a great number of top players who use game tries. The idea is to be a bit more scientific, avoid games that are bad (and avoidable), and bid the good ones. Consistent with other occasions where describing our hand helps us get to good contracts.
Recommendation: I use game tries but I don't have a strong view on it, I think there are merits to both approaches and am hesitant to say strongly which approach is better - it might also have to do a bit with style -
Are you someone that likes a bit of a gamble, playing a pressure style of bridge?
Are you someone that prefers a more scientific approach and wants to be more consistent about being in technically sound contracts?
Back to game tries, there are two methods that are common for game tries.
Short suit game try
This is a method where you bid your short suit as a mode of inviting. Partner is now easily able to evaluate their hand by asking themselves two questions.
1. Am I minimum or maximum - invites tend to need a non-minimum partner to accept
2. Do I have many points in partner's shortage or not? Points opposite shortage are bad for declarer's prospects. The ideal is to have no points opposite a shortage. Next best is just an Ace. See this article on a detailed discussion of points opposite shortage: Points opposite Shortage: Part 1 - Fundamentals.
Lets take some examples
On this sequence South invites partner to game, putting partner in an excellent position to decide what to do, for example if this is the full hand, we put on the brakes and stop in 3♠, which may be in trouble - while 4♠ may have no chance.
However, contrast it with this hand where no points are wasted in clubs.
Only 8 points but game is excellent - due to not having wastage in clubs.
Long suit game try (also known as help suit game try)
This is a situation where you bid a long suit, typically headed by 1 or maximum two honors. Again putting partner in a good position to judge their hand.
What is a good hand to have when partner makes a long suit game try?
1. Values in that suit are good
2. Shortage is also good, singleton or doubleton.
What is bad to have opposite a long suit game try?
1. three small cards, or 4 small cards. These are very poor holdings - often you will have 3 losers in the suit.
Lets look at some examples
Here we show our long and patchy club suit, a suit that needs some help.
This would be a good game, if partner had say
The ♣K and ♣J are excellent, they turn the club suit into 3 winners instead of 0 and reduce the possible losers from 3 to 1 - they do a lot of heavy lifting.
Game is more likely than not, basically on one of two finesses.
But contrast with this hand where we swap the club and diamond values, now game is very poor
Now game is very poor, we have 1-2 club losers maybe even 3. We have 1-2 diamond losers, and we haven't gotten started on the majors..
Conclusion
As you can see, it is very important where our values are located - are they opposite partner's shortage or opposite partner's strength and length - honors combine well together, again I suggest reading Points opposite Shortage: Part 1 - Fundamentals, a well placed King can bring an entire suit to life.
Recommendation
I personally play short suit game tries so perhaps am a bit biased towards that, but I think all approaches are very reasonable - including the style of just "bashing" game, without bidding a trial bid.
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