Rodriguez, starting in place of injured starter Brendan Ryan, had his right hand heavily bandaged afterward and teammates said he'd suffered pretty nasty cuts in three different places.
"He got spiked pretty good out there in a couple different spots on his hand, so we'll have to see how he is after we take a good look at him," said manager Eric Wedge.
Rodriguez had to reach back to get Valencia on a stolen-base attempt with one out in the ninth, making the tag with his glove as the Twins third baseman caught his other hand with his lead foot.
Rookie Kyle Seager, who had been at third base, finished the game at shortstop as fellow rookie Alex Liddi came in at third.
With Ryan remaining back in Seattle to have treatment on a disk problem in his neck, Seager now appears to be the only healthy shortstop option for the time being. The Mariners have six games remaining, three at Texas before closing out with a home series against the A's.
Wedge said before the game that he wanted to see more of Seager up the middle before the season ended and it appears he'll now have no choice in that matter unless Rodriguez is able to return quickly.
Rodriguez went 1-for-4 before his injury and is hitting .202 in 109 at-bats for the season.