2022 - Position 15

XGID=-BaAcCBBBB-------c-db-b-A-:1:-1:1:11:0:0:3:0:10

Unlimited Games. How should Red play 11?

Red must play 3/2*/1 with two of the aces to take a tempo from White. What about the other two aces?

The key in such positions is to keep as solid a prime as you can and so the correct play is 9/8(2). This keeps four White checkers behind a four-point prime and give Red his best chance of winning the game.