DENVER — Kansas City Chiefs quarterback Patrick Mahomes arrived long before Monday night, of course.

But if there was any doubt about his legitimacy, any concern that maybe this was just a small-sample size mirage, that’s over now. Mahomes is a star. Right now.

This wasn’t Mahomes’ best night, but he persevered. The Broncos threw everything at him, and it still wasn’t enough. Down 10 points, on the road on a night that the Chiefs’ offense was held mostly in check, Mahomes rallied the Chiefs for a 27-23 win. For anyone watching Mahomes for the first time, on the “Monday Night Football” stage, it had to be impressive.

And the best play of all wasn’t even with his cannon right arm.

Patrick Mahomes’ left-handed throw keeps a key drive alive

On a huge third-and-5 with a little more than three minutes left and the Broncos leading 23-20, one of Denver’s many blitzes flushed Mahomes left. He had no options on a full sprint to that side of the field. So he threw it left handed.

Mahomes somehow hit Tyreek Hill for 6 yards and a first down using his left hand. It was the type of sandlot play that even Brett Favre would enjoy.

It was clear what was coming next. Mahomes hit a 35-yard pass to Demetrius Harris to get the Chiefs in the red zone. Then Kareem Hunt scored with 1:39 to give the Chiefs the lead.

It was the kind of fourth quarter that makes quarterbacks famous.

Broncos offense plugs away, builds a lead

While the Broncos’ defense was throwing everything it had at Mahomes, Denver’s offense churned out enough to build what looked like a comfortable lead through the first three quarters.

Aside from one 42-yard pass to impressive rookie receiver Courtland Sutton, most of the offense came from the running game in the first three quarters. Rookies Phillip Lindsay and Royce Freeman are much different backs, but the big Freeman scored on a nifty 14-yard run in the second quarter, and the undersized Lindsay plowed in from 1-yard in the third quarter. The latter score gave the Broncos a 20-13 lead.

Denver won’t have an exciting, explosive offense with quarterback Case Keenum, but it can still be effective at times. But it couldn’t put Mahomes away.

Broncos have aggressive game plan against Mahomes

Mahomes couldn’t get much going early on, with just 65 yards in the first half, though his rushing touchdown in the second quarter was big. Denver kept him guessing with a variety of blitzes, and for the first time all season Mahomes looked rattled.

But Mahomes was the best player in the NFL through three weeks for a reason. He started to warm up as the second half went on, and with 6:27 left his short touchdown pass to Travis Kelce cut Denver’s lead to 23-20. Then the Broncos went three-and-out, and Marquette King had a poor punt as he tried to steer it away from Hill. That set up the game-winning drive for Kansas City.

This was the biggest moment of Mahomes’ short career, and somehow he had the guts to improvise and throw his left-handed pass to Hill to keep the key drive alive. After Hunt’s go-ahead score, the Broncos marched downfield and Keenum had Demaryius Thomas wide open down the sideline for what looked like a possible touchdown, but Keenum overthrew it. The Chiefs ended up holding on.

Mahomes came into Monday night’s game as the star of the young NFL season, and what happened in the fourth quarter against Denver might take him to an even higher level.

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Frank Schwab is a writer for Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter!
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