提前锁定冠亚军
ensure a one-two finish

7月29日，中国羽毛球混双两对选手在半决赛中均战胜对手，提前锁定该项目的金银牌。
China has ensured a one-two finish in badminton mixed doubles after two Chinese pairs beat their respective opponents in the semifinals on Thursday.

“Ensure a one-two finish”的意思就是确保了决赛中第一和第二名的位置，即“提前锁定金银牌（冠亚军）”。