The San Francisco Giants received discouraging news regarding one of their starting pitchers before Friday's series opener against the Los Angeles Angels as right-hander Trevor McDonald was diagnosed with a moderate UCL sprain in his throwing elbow.

McDonald exited Monday's start after experiencing discomfort that was initially described as a right elbow strain. Additional imaging conducted later in the week revealed the more serious diagnosis, prompting the organization to seek further evaluation.

The 25-year-old is scheduled to receive a second opinion over the weekend, which should help determine the next steps in his recovery and whether surgery or another treatment plan will be necessary.

Manager Tony Vitello acknowledged the uncertainty surrounding McDonald's timeline and suggested the outlook for the remainder of the season is not encouraging.

While the Giants are waiting for another medical evaluation before making any definitive decisions, Vitello indicated McDonald is expected to miss significant time regardless of the final treatment recommendation.

The injury comes at a difficult point in the season for both McDonald and the Giants. San Francisco has struggled to find consistency during a challenging stretch of the schedule; up until last night, the Giants had a five-game losing streak.

One of the main concerns with McDonald being out is who the Giants will turn to in the rotation. The Giants can move in a multitude of routes but, until the Giants get a clear diagnosis, they will have to play the hand they have been dealt and move accordingly to how long McDonald will be out.

McDonald had become a regular member of the rotation this season, making 14 starts while providing valuable innings for a pitching staff that has dealt with its share of injuries throughout the year.

Across 70.1 innings, the right-hander owns a 5.12 ERA with 57 strikeouts. While the results have been uneven at times, he has continued to take the ball every fifth day and provided needed stability in the rotation before the elbow injury halted his season.

A moderate UCL sprain often requires an extended rehabilitation process, and the outcome of McDonald's second opinion will ultimately determine whether he can avoid surgery. Even in the most optimistic scenario, his return before the end of the regular season appears increasingly unlikely.

For a Giants club attempting to recover from a disappointing road trip and remain competitive down the stretch, the potential loss of another starting pitcher represents another significant obstacle as the season enters its final months.

Don't miss out on our ROUNDTABLE community and the latest news!

It's completely free to join. Share your thoughts, engage with our Roundtable writers, and chat with fellow members.

Download the free Roundtable APP, and stay even more connected!