The San Francisco Giants have placed ace right-hander Logan Webb on the 15-day injured list with right knee bursitis, a move that will test the depth of the rotation for the next few weeks.

Webb was scratched from his scheduled start Monday against the Los Angeles Dodgers after experiencing knee discomfort during his last outing on May 5 against the San Diego Padres. In that game, he failed to complete five innings for the first time this season, allowing six runs over four innings on just 62 pitches.

The IL stint is retroactive to Wednesday, May 6, meaning Webb is eligible to return as early as May 21. However, manager Tony Vitello indicated the team expects Webb to miss only the minimum amount of time, ideally sitting out just two turns through the rotation.

"What's best in the long run is a difficult conversation with him because he wants to man up," Vitello said, describing the process of convincing Webb to go on the IL as "pulling teeth." "He has manned up, and I think thrown more than anybody the last couple years."

Webb acknowledged the knee issue wasn't a new development. "I've dealt with it for a little while, but it's still no excuse," he said after his last start.

In Webb's absence, the Giants have recalled right-hander Trevor McDonald from Triple-A. McDonald made a spot start earlier this season, impressing with seven innings of one-run ball. For a Giants team that has relied heavily on Webb's durability, this injury provides an opportunity for younger arms to step up and prove themselves at the big-league level.

For now, Giants fans can breathe a sigh of relief knowing the timeline appears manageable. If all goes according to plan, the ace should be back on the mound before the end of May, ready to anchor the rotation for the long haul.