Partner opened and I had the above hand. I have 10 HCP but, unfortunately, East has interrupted with my diamond suit. I ruled out the double, but I thought about 1S, 1NT or 2NT. Curious as to your thoughts. We were vulnerable.
This type of auction comes up more often than people would think. When it happens to me, there are a number of things I have to consider. First, I can pass and hope partner reopens with a double. (Remember a double would be a negative double, so that’s ruled out right away). Second, if we have game somewhere and since we are vulnerable and they are not, we would have to set the opponent 4 tricks. Since we are at the 1 level, that may be too much to expect. So I would rule that out. As a result, I will bid normally. In most hands which are opened with a minor, the partnership is looking for a major suit fit, or opts for No Trump once it is determined that a major suit fit is not available. If I were to bid 1NT or 2NT in this instance, partner will never believe I have 4 spades and we could miss a spade fit. So, third, my response will be 1 Spade. (This bid is forcing one round and really is unlimited in HCP, hence partner cannot pass). The auction should proceed normally from there. If we do not have a spade fit, then I may be able to introduce NT later in the auction. For example, if partner bids 2 clubs over 1 spade, then I will bid 3 clubs, showing about 10 points. I would not bid NT since I don’t have hearts stopped or partially stopped. Partner may not have hearts stopped either. Now if partner probes with a 3D or 3H bid, I can bid 3NT.
So first, tell partner you have 4 spades. Then, try to show partner you have about 10 HCP, then show partner you have diamonds stopped. That would be the order of bidding you should use on this hand.