Chicago @ Colorado preview

Last Meeting ( Aug 19, 2016 ) Chi. Cubs 6, Colorado 7

As opening assignments go, it doesn’t get much tougher for Colorado Rockies top prospect Jeff Hoffman, who will make his major-league debut Saturday against the visiting Chicago Cubs. Hoffman is being asked to slow down a dominant Cubs team that has won 18 of its last 22 games and owns the third-best offense in the majors.

The 23-year-old Hoffman was acquired from Toronto last season in the trade involving Troy Tulowitzki and has gone 6-9 with a 4.02 ERA in 22 starts at Triple-A Albuquerque this season. “Into the fire, but we feel like Jeff can handle it,” Rockies manager Walt Weiss told reporters. “He’s got plenty of stuff. It’s plus stuff, even at the major-league level. He can navigate lineups with his stuff alone. I feel like he’s ready for this.” Chicago began a nine-game, 10-day road trip with Friday’s 11-inning, 7-6 loss to the Rockies but has the majors' best record and a commanding lead in the National League Central. Manager Joe Maddon has given Jason Heyward the weekend off in hopes the rest will help the veteran snap out of a 6-for-41 slump when he rejoins the lineup Monday in San Diego.

TV: 8:10 p.m. ET, CSN Chicago, ROOT (Colorado)

PITCHING MATCHUP: Cubs LH Mike Montgomery (4-5, 2.43 ERA) vs. Rockies RH Jeff Hoffman (MLB Debut)

Montgomery has been summoned from the bullpen to start in place of John Lackey, who was placed on the disabled list Friday with shoulder soreness. The 27-year-old Montgomery was acquired from Seattle on July 20 and has appeared in seven games for Chicago out of the bullpen. Montgomery, who never has faced Colorado, owns a 5-7 record and 4.44 ERA in 18 career starts - including two shutouts last season.

Hoffman is taking the rotation spot of Tyler Chatwood, who landed on the disabled list because of a mid-back strain. The 6-5 native of New York posted a 3.03 ERA with 75 strikeouts and 27 walks over 100 innings in 2015 while pitching in Single- and Double-A. Hoffman earned his major-league recall after throwing nine scoreless innings over his last two starts in the hitter-friendly Pacific Coast League.

WALK-OFFS

1. Colorado CF Charlie Blackmon was scratched from Friday’s starting lineup due to a bruised right toe but appeared as a pinch-hitter in the 10th inning.

2. The Cubs placed RHP Hector Rondon (triceps) on the disabled list and recalled LHP Rob Zastryzny and RHP Felix Pena from Triple-A Iowa.

3. The Rockies activated RHP Chad Qualls from the DL and optioned RHP Carlos Estevez to Triple-A Albuquerque.

PREDICTION: Cubs 7, Rockies 4