"Adrian Beltre will miss three more weeks after an MRI indicated that he aggravated his strained left hamstring Saturday afternoon.

The Texas Rangers third baseman grabbed his leg after rounding first base about midway through his second consecutive day running the bases in advance of a medical rehabilitation assignment.

He walked into the outfield, slapped his head with both hands, and tried to collect himself in shallow right field. Beltre was limping as he went to the dugout.

Dr. Keith Meister evaluated the injury, first suffered July 23, around 6 p.m., and an MRI was performed. It showed a new Grade 1 strain.

"I told you hamstrings are fickle," said manager Ron Washington, who didn't believe the Rangers were attempting to rush Beltre back too soon. "You have to go through baseball activities to check it. Start, stop, go, move your quick-twitch muscles."

The Rangers entered Saturday with a 5-7 record without Beltre, including 1-3 against left-handers. Beltre, a right-handed hitter, was second in the American League in RBIs (76) when he was injured. Michael Young, Chris Davis and Andres Blanco have all logged games at third in Beltre's absence. Davis has been traded, so the bulk of the remaining games without Beltre, a two-time Gold Glove winner at the position, will fall to Young."