Sean Sullivan gets the ball for the Rockies after a tidy 3-inning, 0-run no-decision in his MLB debut against the Athletics on June 12. He's a low-three-quarters lefty with an 89 mph fastball and a deception-over-stuff profile — exactly the kind of arm Wrigley's afternoon shadows can either swallow or expose. Javier Assad counters at 4-1 with a 3.99 ERA, fresh off 6 shutout innings against the Giants on his last turn.
The Rockies are 28-46 and that's the polite version. But they punched back Tuesday night 5-2 to even this series after dropping the opener 5-4, and Colorado's outfield situation makes the road win feel even stranger: Brenton Doyle, Jordan Beck, and Mickey Moniak are all on the IL, Kris Bryant is still shut down with the back, and Chase Dollander is staring at UCL surgery. They're scraping the roster together and still found a way to grab a game at Wrigley.
- Day-To-DayBrayan Castillo RP — The Rockies announced Monday that Castillo is dealing with right lat tightness and has been shut down from throwing while undergoing treatment for the injury, TheDNVR.com reports.
- Day-To-DayCase Williams SP — Williams is currently slowed by a stress reaction in his right triceps, Thomas Harding of MLB.com reports.
- Day-To-DayJared Thomas CF — The Rockies announced Monday that Thomas hasn't been participating in spring training while he recovers from offseason surgery to address a fractured hamate bone in his right wrist, TheDNVR.com reports.
- 10-Day-ILBrenton Doyle CF — Doyle (oblique) worked in the batting cage Monday, MLB.com reports.
- 10-Day-ILJordan Beck LF — Beck (hamstring) stretched and did running drills prior to Tuesday's game against the Cubs, MLB.com reports.
- 10-Day-ILMickey Moniak LF — Moniak (ankle) will begin a rehab assignment with Triple-A Albuquerque on Thursday, MLB.com reports.
- 15-Day-ILJimmy Herget RP — The Rockies sent Herget (shoulder) to Triple-A Albuquerque on Tuesday to begin a rehab assignment.
- 15-Day-ILTanner Gordon RP — Gordon (0-1) took the loss Sunday, allowing four runs on six hits and a walk over three-plus innings against San Francisco. He struck out two.
- Day-To-DayEdward Cabrera SP — Cabrera (4-3) notched the win over Colorado on Thursday, allowing two runs on five hits and two walks while striking out five batters over 5.1 innings.
- Day-To-DayJaxon Wiggins SP — The Cubs announced Wednesday that Wiggins (elbow) has resumed throwing bullpen sessions and facing hitters at the organization's complex in Arizona and could soon be ready to pitch in games, MLB.com reports.
- Day-To-DayBrandon Birdsell RP — Birdsell (elbow) will miss the entire 2026 season, Jim Callis of MLB Pipeline reports.
- Day-To-DayJeff Brigham RP — Brigham was placed on the 7-day injured list at Triple-A St. Paul, retroactive to April 6, with a left oblique strain, TwinsDaily.com reports.
- 15-Day-ILDaniel Palencia RP — Palencia (2-1) worked around a walk to toss a scoreless inning of relief and earn the win in Monday's 5-4 victory over the Rockies. He struck out three.
- 15-Day-ILMatthew Boyd SP — Boyd (knee/shoulder) will throw an up-down bullpen session Tuesday, Meghan Montemurro of the Chicago Tribune reports.
- 15-Day-ILJameson Taillon SP — Taillon (hamstring) is expected to be sidelined until after the All-Star break, Vinnie Duber of the Chicago Sun-Times reports.
- 15-Day-ILRiley Martin RP — Martin has been diagnosed with flexor strain in his left elbow and is expected to miss eight weeks, Taylor McGregor of Marquee Sports Network reports.
Chicago sits at 38-36 and the rotation is held together with tape. Justin Steele, Matthew Boyd, and Jameson Taillon are all on the shelf — Taillon won't be back until after the All-Star break — and closer Daniel Palencia hit the 15-day IL this week too. Assad has been the steady hand inside that mess, and the Cubs need him to be that again with the bullpen thinner than they'd like.
First pitch is 7:05 PM CT. The market reads this as a get-right spot for Chicago at -180, which would give them the series win and a little breathing room before the weekend. The Rockies' play is the same as always on the road: scratch a couple early, hope the kid eats some innings, and ride it out.
The angle worth watching is how the Cubs' lineup handles Sullivan the first time through. Low-slot lefties with command can steal a start before a team's video room catches up, and if Sullivan flashes the same control he had against Oakland (0 walks, 2 strikeouts), this gets interesting in a hurry. If he doesn't, the Cubs are home, well-rested, and very capable of putting up a crooked one early.