SAN FRANCISCO — The Giants announced on Tuesday afternoon that two-time All-Star Logan Webb is scheduled to make his return from the 15-day injured list on Friday, when he’ll start against the Colorado Rockies at Coors Field.

Webb, who threw a bullpen on Tuesday, hasn’t made a start since May 5, when he was limited to a season-low four innings against the San Diego Padres, due to right knee bursitis. His stint on the injured list is retroactive to May 6.

“I think, more than anything, the sequence he needed to go through the exercises necessary in the training room, and then also to do some of the things he wanted to do in the ‘pen,” Giants manager Tony Vitello said, when asked why Webb was starting on Friday instead of this afternoon. “This weekend makes everything a little bit better for a bunch of different reasons, but mainly centered on his routine and what he needed to go through.”

The right-hander struggled before hitting the injured list, posting a 5.06 ERA over his first eight starts this season.

With Webb nearing his return, the Giants will soon have to decide what they do with right-handers Tyler Mahle and Trevor McDonald, who were scheduled to start on Tuesday and today, respectively, against the Diamondbacks.

The 31-year-old Mahle, who signed a one-year, $10 million free-agent deal with the Giants this offseason, has been one of the worst starters in the majors this season, posting a 6.10 ERA over his first 10 starts.

McDonald, 25, had a rough start Friday night against the Chicago White Sox (3 2/3 innings, seven earned runs) that inflated his ERA to 4.76. But the right-hander allowed just five earned runs in his first three starts this season.

Worth noting

Right fielder Jung Hoo Lee was scheduled to begin baseball activities on Tuesday. Lee is currently on the 10-day injured list due to a mid-back strain and could potentially return to the team this weekend, per Vitello.

Outfielder Jared Oliva (left wrist hamate fracture) is taking batting practice this week. He will join Triple-A Sacramento this weekend to begin a rehab assignment.