The St. Louis Cardinals might be without one of their former top prospects for an extended period. Outfielder Jordan Walker injured his left knee during the third inning of yesterday’s 6-4 Spring Training win over the Washington Nationals. He will be evaluated this week. Walker hit .201 with five home runs and 20 RBI in 51 games last season. In other team news, the Cardinals also beat the Mets 6-1 in exhibition play yesterday. Sonny Gray starts for St. Louis against Houston today.