OAKLAND -- Right-hander Matt Shoemaker, the Toronto Blue Jays¡¯ top starting pitcher this season, sprained his left knee during Saturday¡¯s 10-1 victory over the Oakland A¡¯s and will undergo an MRI to determine the injury¡¯s extent.

¡°Hopefully it¡¯s not that bad,¡± Blue Jays manager Charie Montoyo said, striving to remain optimistic.

Toronto right-hander Sam Gaviglio, who relieved Shoemaker and struck out five in four perfect innings, likely would replace Shoemaker in the team¡¯s starting rotation if a fill-in becomes necessary. Gaviglio admitted that ¡°it would be a very big loss¡± if Shoemaker, 3-0 with a 1.57 ERA in five starts, were to be sidelined for a prolonged period of time. Added Gaviglio, ¡°He¡¯s been strong every outing.¡±

Shoemaker blanked Oakland for three innings and appeared to make his life easier by trapping Matt Chapman off first base with a pickoff throw. But the Blue Jays couldn¡¯t corral Chapman as quickly as they wanted to, prompting Shoemaker to join the defenders in the rundown. Shoemaker made the inning-ending tag, but as he did so, his left leg either buckled or planted itself in some loose turf.

Montoyo acknowledged that Shoemaker violated a fundamental rule by joining the rundown. ¡°You never want to see the pitcher involved,¡± Montoyo said. But, he added, ¡°[Shoemaker¡¯s] a gamer. He got in there because he wanted to get the out.¡±

On came Gaviglio, who demonstrated his stamina should the team need a starter in place of Shoemaker. ¡°That¡¯s one of the reasons that he pitched four innings,¡± Montoyo said.

Gaviglio, who ranked second among Blue Jays pitchers with 24 starts last year, sounded ready to return to that role if needed. ¡°Whatever they tell me to do, I¡¯ll do my job,¡± he said after the longest relief outing of his career.