Mariners center fielder Julio Rodríguez returns to the lineup for Saturday's game

SEATTLE — Seattle center fielder Julio Rodríguez, who was placed on the seven-day injured list July 3 because of a concussion, was activated Saturday and rejoined the Mariners’ lineup against the San Francisco Giants.

Rodríguez, a three-time All-Star, will serve as the Mariners' designated hitter and bat second. To clear room for him, the Mariners designated utilityman Miles Mastrobuoni for assignment.

Rodríguez was struck by a ball in the back of the head in a 1-0 victory over the Los Angeles Angels on July 2. He took part in pregame drills, ran the bases and took swings off a pitching machine Friday, general manager Justin Hollander said.

“It’s been a couple of weeks, he hasn’t done a lot of the things that you need to do in terms of full pregame, full activation, that sort of stuff. So, we’ll see where he is after today," Hollander said. “I would be hopeful that he’ll be ready to go tomorrow, but I don’t know that, and we’ll just see how he feels after the full pregame today.”

Rodríguez played in a career-high 160 games last season. He had played in 87 games this season, hitting .259 with 15 doubles, 14 home runs, 40 RBIs and 12 stolen bases.

Meanwhile, All-Star utilityman Brendan Donovan started a rehab assignment for Triple-A Tacoma on Friday. Donovan was placed on the 10-day injured list with a left groin muscle strain in May.

The 29-year-old Donovan appeared in a game for the Mariners’ Arizona Complex League team on Wednesday, going 0 for 3 with three strikeouts and a walk.