Cubs’ Pitching Depth Tested As Caleb Thielbar Becomes Eighth Pitcher On IL

The Chicago Cubs’ pitching staff continues to face significant disruption, with another key reliever joining the injured list just as the team prepares for a high-profile series against the Los Angeles Dodgers. Veteran left-hander Caleb Thielbar was placed on the IL on Friday due to a mild hamstring strain.

The move, confirmed by manager Craig Counsell, adds to a rapidly growing list of pitching injuries that have tested Chicago’s depth throughout the month. The timing is particularly challenging given the Cubs’ current position in the standings and upcoming schedule.

Despite the setbacks, Chicago enters its series against the defending champions in strong form, carrying momentum from a lengthy winning streak. However, the availability of its pitching staff remains a central concern.

Thielbar’s injury underscores a broader trend for a team that began the season with expectations of rotation stability but has instead been forced into constant adjustments.

1. Injuries Pile Up Across Pitching Staff

Thielbar becomes the eighth Cubs pitcher to land on the injured list this month, highlighting the scale of the team’s current pitching issues. The list includes multiple key contributors across both the rotation and bullpen. Among those sidelined are Cade Horton, Daniel Palencia, Phil Maton, Hunter Harvey, Ethan Roberts, Porter Hodge, Matthew Boyd, and Jordan Wicks. Horton’s absence is the most significant long-term loss, as he is set to undergo Tommy John surgery and miss the remainder of the season. The frequency of injuries has forced the Cubs to constantly adjust bullpen roles and starting assignments. Depth options have been elevated earlier than expected, placing additional pressure on younger arms. What was initially viewed as one of the more reliable pitching groups in the league has instead become an area of ongoing instability.

2. Strong Season Start Amid Rotation Challenges

Even with the mounting injuries, the Cubs remain one of the strongest teams in the National League standings. Chicago currently sits at 16-9 and is tied for first place in the NL Central. The team has also built momentum through a nine-game winning streak, which continues into a challenging series against the Los Angeles Dodgers. The stretch has helped offset some of the concerns surrounding pitching availability. Right-hander Jameson Taillon is scheduled to start Game 1 of the series against Dodgers pitcher Emmet Sheehan. His performance will be closely watched given the current strain on the pitching staff. The contrast between on-field success and roster instability has defined the Cubs’ early-season narrative.

3. Thielbar’s Role And Career Background

Before his injury, Thielbar had been a steady presence in the Cubs’ bullpen. He posted a 2-2 record with a 3.12 ERA, providing reliable middle-relief innings. His most recent appearance came in a narrow win over the Philadelphia Phillies, where he allowed one hit and one run in a high-scoring contest. That outing proved to be his last before being placed on the IL. Thielbar’s MLB career dates back to 2013, when he debuted with the Minnesota Twins. He has since had two separate stints with Minnesota, along with time in the minor league systems of the Detroit Tigers and Atlanta Braves. Chicago acquired him in December 2024 on a one-year deal, and he delivered a solid season with a 3-4 record, 2.64 ERA, and 56 strikeouts before re-signing on a $4.5 million contract for 2026.