Patrick Mahomes has been rehabbing from a torn ACL suffered last season with the intention of being under center for the season opener against the Denver Broncos and the latest update signals the two-time MVP will be suited up for Monday Night Football.Kansas City Chiefs head coach Andy Reid said Mahomes has a, “pretty good,” chance of starting week 1.The update is positive for Mahomes Fantasy managers, but does that mean placing Mahomes in the starting lineup against one of the best defenses in the NFL?Reid: Patrick Mahomes (knee) has "pretty good" chance to start Week 1.— Underdog NFL (@UnderdogNFL) September 8, 2026Patrick Mahomes’ Week 1 Fantasy OutlookMahomes regained his upper-echelon Fantasy production as the three-time Super Bowl winner ranked as QB 2 prior to his injury. While Mahomes displayed an ability to churn out Fantasy points throughout the season, the Broncos defense proved to be a problem for Mahomes in their lone matchup last season. Mahomes was limited to a pedestrian performance against the Broncos, finishing with 14.3 Fantasy points.Patrick Mahomes is likely to start against Denver unless an issue arises in the next few days.Andy Reid: “As far as our roster goes, pretty good chance that Patrick will go ahead and start unless something were to come up here in the next couple days, but most likely, he'll be… pic.twitter.com/GW0qdiApJ6— MicNuggets (@micnuggetsnfl) September 8, 2026The Broncos defense is a tough matchup for Mahomes to make his return against as all the metrics are against the six-time Pro Bowler’s Fantasy outlook. Denver ranked third in points per game allowed and second in yards allowed per game last season. The stalwart defense really showcased itself in the QB matchup, as the Broncos defense limited opposing quarterbacks to 15.1 FPPG last season, which ranked at the 25th worst matchup for QBs.On top of the tough matchup for his first action since the ACL tear, the game conditions will also be a factor in Mahomes’ return. There’s a 65% chance of rain with wind gusts up to 17 miles per hour forecasted for the Monday-night contest. The mix of playing one of the NFL’s toughest defenses with an ugly weather forecast creates an environment for Fantasy points being tough to come by in Mahomes’ return to action. Mahomes Fantasy managers may want to hold off starting the former MVP until week 2’s matchup against the Indianapolis Colts. A healthy Mahomes didn’t light up the Broncos defense last season and it’s tough to see that happening in Mahomes’ first action since the ACL tear. Mahomes Fantasy managers should start their backup QB in week 1 then let the three-time All Pro loose for the rest of the season. If a Fantasy manager doesn’t have a backup or doesn’t like their backup’s matchup, there are plenty of options on the waiver wire to fill in for week 1. Kirk Cousins, Malik Willis and Bryce Young aren’t names to get excited about in season-long formats, but they can fill the need for Mahomes Fantasy managers in week 1. Each QB is rostered at 11.4% or less and should be available on the waiver wire in the majority of leagues. These quarterbacks aren’t facing one of the best defenses in the NFL either as each of their opponents gave up at least 24.4 points per game last season. The news of Mahomes gearing up for a week 1 start is exciting for Mahomes Fantasy managers, but he should be left on the bench for week 1 against a difficult opponent. More Fantasy Sports on SI NewsAdd us as a preferred source on GoogleFollow