Alou walked off the field with trainer Ray Ramirez in the fifth inning after advancing to second base on an infield out. He had also been on base in the first inning during the Mets' four-run rally. Alou also extended his hitting streak to 22 games with a single.
Alou, 41 and oft-injured, was assigned to the disabled list from May 13-July 27.
Alou said that he felt an odd sensation in the muscle, but not pain. At first, he characterized it as "stiffness." Later, Alou withdrew that self-prognosis.
The veteran took treatment and told manager Willie Randolph: "Don't count me out for [Wednesday]."
Marty Noble is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.