That's a reasonable approach to take, but I imagine his defense would be, "If I were suspended for 10 games you would keep me. If I were suspended for 50 games you would keep me. This is only a matter of degree, so you should keep me if it's just a bit longer than that." The team would have to have a stronger argument, such as "you brought dishonor upon the organization."
The question then is whether a year's suspension is a material breach of the contract. That's a question of fact for a jury. Do you think A-Rod is likely to get a sympathetic jury in NYC?