To solve this question, the user needs to understand the grammar rules for conditional sentences. The sentence is in the past tense, which suggests that the answer choice needs to be in the past tense as well.

Now, let's go through each option and explain why it is right or wrong:

A. had played: This option is correct. The sentence expresses a hypothetical situation in the past that did not happen. Therefore, the correct option should be in the past perfect tense. "Had played" is in the past perfect tense, which is appropriate for the given sentence. So, option A is the correct answer.

B. will play: This option is wrong. This is in the future tense, which is not appropriate for the given sentence. The sentence refers to a hypothetical situation in the past, so the verb tense must be in the past.

C. have played: This option is wrong. This is in the present perfect tense, which is not appropriate for the given sentence. The sentence refers to a hypothetical situation in the past, so the verb tense must be in the past.

D. will have played: This option is wrong. This is in the future perfect tense, which is not appropriate for the given sentence. The sentence refers to a hypothetical situation in the past, so the verb tense must be in the past.

Therefore, the correct answer is: A. had played