INDIANAPOLIS — The Indianapolis Colts have picked themselves up off the mat again.

Frustrated and under siege after an ugly start in a tie against the Houston Texans and a loss to the Jacksonville Jaguars, the Colts came roaring back with a 20-17 victory against the Kansas City Chiefs to get into the win column for the first time this season.

The game was sealed by Rodney McLeod’s interception off a Stephon Gilmore deflection of a Patrick Mahomes pass to hand the Chiefs their first loss of the season.

How the Colts pulled off the upset on Sunday afternoon at Lucas Oil Stadium:

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1. When the Colts had to have it, Matt Ryan made a play

Matt Ryan has been far from perfect so far as the Colts’ starting quarterback.

Under pressure throughout the day, Ryan struggled and fumbled twice, both of the fumbles leading to Kansas City touchdowns.

But Indianapolis traded for Ryan in part because he’s a professional, and he has been great in crunch time twice this season, the first to give the Colts a shot against Houston, the second to give Indianapolis a win against the Chiefs.

Helped out by an unnecessary roughness penalty, Ryan marched the Colts 76 yards on 16 plays, taking nearly the entire fourth quarter to get there, and then fired a strike to Jelani Woods for the go-ahead touchdown, finishing 27 of 37 for 222 yards and two touchdowns.

2. The Colts defense came to play

Facing off against one of the best quarterbacks in the NFL, the Indianapolis defense turned in its best performance, keyed by its defensive line.

On the surface, the numbers didn’t look all that great. The Colts sacked Mahomes once and hit him four times.

But Mahomes is one of the league’s best at avoiding pressure, and he made the numbers look better than they actually were. Fully healthy after dealing with a strained adductor in his hip against Jacksonville, DeForest Buckner was dominant inside, repeatedly forcing Mahomes off of his spot, making four tackles and stuffing Kansas City at the goal line to force a field goal instead of a touchdown.

Yannick Ngakoue made his first big play, sacking Mahomes and adding another hit.

For the most part, though, the defensive line didn’t have to hit Mahomes to gum everything up. Indianapolis forced him to pull the ball down, hold onto it and scramble around, keeping him from throwing in rhythm, and gave the Colts a chance to come back at the end.

Then Gilmore sealed it, deflecting a Mahomes pass into the hands of McLeod for the game-sealing interception.

3. Bubba Ventrone’s special teams won their battle

The Colts take a lot of pride in special teams.

And it kept them in the game Sunday.

Ashton Dulin and Kylen Granson got it started. After an ugly three-and-out to start the game, Colts punter Matt Haack lofted a high, spiraling punt into the clear sky with the Lucas Oil Stadium roof open, and Dulin blew away his blocker to put pressure on Kansas City rookie punt returner Skyy Moore.

Moore muffed the punt, and Granson dove on it, setting up the Colts at the 4-yard line for a touchdown.

Granson made the next play, downing another Haack punt on the half-yard line to nip a Chiefs drive in the bud.

Indianapolis kept it up. Chase McLaughlin buried both of his field goal attempts, including a 51-yarder, on a day when Chiefs fill-in Matt Ammendola missed an extra point and a field goal, and when the Chiefs tried a fake, the Colts were all over it.

The holder, punter Tommy Townsend, picked up the ball and tried to throw it, but Bobby Okereke was in perfect coverage.

4. The highest-paid offensive line in the NFL still isn’t playing to its paycheck

Under Chris Ballard, the Colts’ organizational mantra has been to build the team through the offensive and defensive lines first.

To that end, Ballard has made the Indianapolis offensive line the highest-paid in football, handing out big-money contracts to left guard Quenton Nelson, center Ryan Kelly and right tackle Braden Smith, although the team gambled at left tackle and right guard this season by going with unproven players at left tackle (former swing tackle Matt Pryor) and right guard (former center Danny Pinter).

The offensive line is supposed to be the strength of the team. When the Colts traded for Ryan, the belief was that he’d have the protection around him that he hasn’t had in Atlanta.

The opposite has happened.

The Colts offensive line has been the team’s weak link, a development highlighted in stark reality by the way Sunday’s game played out. Indianapolis got better play from its defense, its special teams, its wide receivers, but the offensive line kept holding the offense back.

Kansas City put Ryan under duress all day long. The Chiefs sacked Ryan five times, forced two fumbles, hit him seven times overall and repeatedly failed to give running back Jonathan Taylor (71 yards on 21 carries) the room he needed to make a play. Making matters worse, the Colts struggled to pick up blitzes, leading to repeated free rushers who blew up plays.

But the Colts switched to a quicker-strike passing game on the final drive, and the move paid off.