Report: Rangers inquire about Reds' Castillo, Gray, Mahle

The Texas Rangers have been one of baseball's busiest teams this offseason, and it doesn't look like they're finished adding to their roster just yet.

Texas is looking for ways to improve its starting rotation and has inquired with the Cincinnati Reds about trading for one of Luis Castillo, Sonny Gray, or Tyler Mahle, sources told MLB Network's Jon Morosi.

The Rangers have spent $561.2 million on four players - Corey Seager, Marcus Semien, Jon Gray, and Kole Calhoun - this winter, but their inexperienced rotation remains an area of need even after Gray's addition.

Career stats

Rangers starters combined to rank 28th in ERA and FIP and 27th in strikeouts per nine last season. Adding one of Castillo, Gray, or Mahle would likely improve those numbers.

Castillo possesses one of baseball's best changeups. He ranked 12th in strikeouts per nine, 14th in ERA, 15th in fWAR, and 18th in FIP among big-league starters after the All-Star break following a rough first two months last season.

The 28-year-old would also be an affordable option for the Rangers, as he's projected to earn $7.6 million in arbitration. He's also under club control until 2023.

Gray comes with a heftier price tag - $10.1 million in 2022 - but the 32-year-old also has a more polished resume than Castillo or Mahle.

The two-time All-Star has twice finished in the top seven in Cy Young voting. Over the last three seasons, Gray's 3.49 ERA and 10.6 strikeouts per nine are tops among Reds starters with at least 350 innings pitched, according to FanGraphs.

Gray has one year remaining on his contract, which includes a $12-million team option for 2023.

Mahle is coming off a solid campaign, where he tossed a career-high 180 innings. The 27-year-old authored a 13-6 record with a 3.75 ERA, a 3.80 FIP, and 10.5 strikeouts per nine in 2021.

The California native is projected to earn $5.6 million through arbitration and won't become a free agent until 2024.