Felix Hernandez is still feeling tightness in his back two days after slipping on the mound in his start Friday - and he's no certainty to make his next scheduled start.
"He's feeling it today, so tomorrow will be an important day for him," manager Eric Wedge said.
Felix's next start would normally be on Wednesday in Anaheim against the Los Angeles Angels. If he can't go, the Mariners would have to scramble to find a starting pitcher - perhaps trying Hisashi Iwakuma or dipping into the minor leagues for an arm.
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