Randal Grichuk celebrates after hitting a walk-off single to defeat the Chicago Cubs 4-3 on Sunday. (AP Photo/Jeff Roberson) Associated Press ST. LOUIS – Randal Grichuk hit a two-run homer in the eighth inning and a game-ending RBI single in the ninth, helping the St. Louis Cardinals top the Chicago Cubs 4-3 in a wild prime-time opener on Sunday night. Jose Martinez sparked the winning rally with a pinch-hit double against Mike Montgomery, who closed out Chicago’s World Series championship in November.