"I got a little hamstring deal that I did out in Colorado," Mesoraco said. "It's not a bad thing at all. I think [manager Dusty Baker] at this point in the year doesn't want it to be something that lingers around. Just get it out of here and be done with it."
In Sunday's 7-4 loss to the Rockies, Mesoraco tweaked his left hamstring when he lunged for first base running out a ground ball.
"It definitely wasn't bad at all, but I felt it," he said.
Mesoraco had no trouble playing a complete game on Monday, but Ryan Hanigan started the next three games, including Thursday's finale against the Cardinals.
Baker tried to avoid using Mesoraco during Wednesday's 16-inning loss, especially on offense, "because if he runs first to home or first to third, then he could blow it out and be gone for a while."
Mesoraco ended up catching three innings and reached base in the 15th, but he could not move a runner to second base on a bunt.
As Mesoraco has proven, the injury is something he "absolutely" could play through, but Baker decided to err on the side of caution.
"I don't know he'll be all right by the end of the season," Baker said, "but I hope he's better."
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, and follow him on Twitter @m_sheldon. Jeremy Warnemuende is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.