PITTSBURGH — Patrick Mahomes tied a franchise record with six touchdown passes and the Kansas City Chiefs put on an impressive offensive display in a 42-37 win over the Pittsburgh Steelers on Sunday.

The 22-year-old Mahomes finished 23 of 28 for 326 yards in his third career start as the Chiefs (2-0) won in Pittsburgh for the first time since 1986. Mahomes has 10 touchdown passes through two weeks, the most ever by a quarterback through two games in NFL history.

Trevor Kelce caught seven passes for 109 yards and two scores. Tyreek Hill, Chris Conley, Kareem Hunt and Demarcus Robinson also hauled in touchdown passes as the Chiefs recovered in the second half after blowing an early 21-pont lead.

Pittsburgh quarterback Ben Roethlisberger shook off an achy right elbow that limited him in practice during the week, completing 39 of 60 passes for 452 yards and three touchdowns. The 36-year-old also leapt into the end zone for a 3-yard score with 1:59 to go that got the Steelers (0-1-1) within five.

Rather than attempt an onside kick, Pittsburgh sent it deep. Two runs by Hunt gave Kansas City a big first down and Steelers linebacker Tyler Matakevich was flagged for roughing the punter as the Chiefs ended a six-game losing streak in Pittsburgh.

It might be the first of several turnarounds by the Chiefs, who made the surprising decision trade away veteran Alex Smith in the off-season and place the franchise in the hands of untested but strong-armed Mahomes.

So far, so very, very good.

A week after throwing for four scores in a victory over the Chargers, Mahomes picked up right where he left off. He needed just 13 minutes to toss three touchdowns as the Chiefs built a quick 21-0 lead, the last one a flip in the flat to Hunt in which the running back walked through a tackle by rookie safety Terrell Edmunds and into the end zone.

The Steelers received the break they needed to get back into the game when a Roethlisberger fumble that resulted in a Kansas City touchdown was waved off due to a defensive penalty. Pittsburgh reeled off touchdowns on its next three possessions to pull even at the break.

The Steelers stalled a bit in the second half. Mahomes did not.

A nifty toe-tap by Robinson in the back of the end zone put Kansas City up 35-28 with 3:15 left in the third quarter and Kansas City's next possession ended with Mahomes getting the ball to Hill, who darted 29 yards to the end zone.

STATS AND MORE STATS

The six touchdown passes by Mahomes tied the most ever allowed by the Steelers in franchise history. Buffalo Bills Hall of Famer Jim Kelly threw six against Pittsburgh in 1991. ... Pittsburgh tight end Jesse James set a career-high with 138 yards receiving. ... Steelers wide receiver Antonio Brown caught nine passes for 67 yards, becoming the fastest player in NFL history to cross the 750-career reception total (117 games). ... Roethlisberger moved past John Elway and into seventh for career passing yards. ... The Chiefs scored six touchdowns and had just 27:49 time of possession. Their longest scoring drive lasted just 3:57. ... Mahomes' six scores tied Len Dawson's franchise mark set in 1964 against Denver when the Chiefs played in the American Football League.

INJURIES

Chiefs: Get well Eric Berry. The veteran safety remains out with a sore heel and Kansas City's defensive backfield hasn't exactly stepped up in his absence. The Chiefs have allowed 870 yards in the air through two games. Part of the blame — if that's the word — can be placed on opponents playing catch-up after getting buried early by Mahomes and company.

Steelers: Pittsburgh's secondary badly missed cornerback Joe Haden, who sat out with a strained right hamstring. There appeared to be communication issues all over the place early on, particularly when it came to finding a way to guard Kelce.

UP NEXT

Chiefs: Welcome San Francisco to Arrowhead Stadium in their 2018 home opener next Sunday.

Steelers: Head to Tampa Bay for a Monday night meeting with the Buccaneers on Sept. 24.

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