The most important piece to the Cubs' starting pitching mix isn't even in the rotation

Though all the attention was on the trade for Miami Marlins pitcher Edward Cabrera, the Chicago Cubs actually made a few transactions tied to their starting rotation. Shota Imanaga came back via the qualifying offer, and they added some depth at the minor league level in the form of Vince Velasquez and Kyle Wright. However, way back at the beginning of the offseason, they kicked off the winter with a mini-extension, rewarding one of their most important players from the 2025 team — Colin Rea.

Rea wasn't exactly meant to play as sizable a role as he did. He was reunited with Craig Counsell to be a typical swingman, but a rash of starting pitching injuries that caused everyone from Justin Steele to Javier Assad to miss significant time thrust him into regular rotation duties by mid-April. While he wasn't an ace, it's fair to say that the Cubs probably wouldn't have had as good a season as they did if he weren't there. In 159 1/3 innings, the second-highest total of his career, he posted a 3.95 ERA with a 4.11 FIP and averaged the highest fastball velocity of his career at 93.9 MPH.

His ability to anchor a rotation spot when the need arose spurred the Cubs to keep him around for another year and add another club option for 2027, all for $6.5 million guaranteed. That said (fingers crossed), he's unlikely to carry the same level of workload this season. The team has a full rotation to start the year, including Cabrera, Imanaga, Jameson Taillon, Cade Horton, and Matthew Boyd, with Justin Steele set to return a bit sooner than expected after undergoing internal brace surgery last year. Yet, Rea's still a critical piece of the puzzle and is putting in the work to ensure he can continue to be their go-to glue guy.

Even if the Cubs aren't plagued by the same injury woes in the rotation, the reality of a 162-game season is that far more than five starters are needed to get through the year. That may be doubly true this time around. After missing almost all of 2025, it'd be unreasonable to expect Steele to go back to his full workload and intensity immediately. Horton, meanwhile, is still young, just entering his second big-league season after throwing a career-high in innings last year. The Cubs also took on some risk when adding the injury-prone Cabrera. Rea gives them room to take that kind of gamble on a high-upside arm and cover for any missed time.

It's why pitching coach Tommy Hottovy recently told reporters that Rea is preparing for everything this spring.

"He’s a guy we know can start, we know we’re going to stretch him out to a 65-70 pitch mark at camp,” he said. “But also, we know his stuff can play up in shorter bursts in the pen. Colin’s a guy as a starter — if he’s in the pen, you don’t really have to match him up as much. He’s a guy who can go one time through the order, and you’re confident he can get everybody out in the lineup.”

The Cubs have done wonders by tweaking his pitch mix to use his four-seamer far more, and that will continue, as Hottovy added they're now working on his splitter to make it a more consistently competitive offering.

Colin Rea might just be the most important swingman in the league

He didn't pitch much in relief last year, but Rea was sharp overall when he did, only giving up one run in his 16 innings out of the bullpen. The Cubs have done a good job rebuilding their relief corps this year, adding proven veterans like Phil Maton and Hoby Milner, while also bringing back Caleb Thielbar and introducing upside in Hunter Harvey. Yet, with his ability to pitch and adjust to any lineup, it'll help keep everyone fresh if Counsell can continue to lean on Rea consistently for multi-inning outings.

It won't be reflected on the stat sheet, but if the Cubs' starters are still sharp and ready to go by the postseason, a lot of that will likely be attributable to Rea. In the modern era of baseball, it's less about having five starters who remain good throughout an entire season and more about having your five best starters in peak form by the time the playoffs come around. The Cubs understand this, and it's why they're working to make Rea the best version of himself - regardless of his role.