Patrick Mahomes’ epic start to the 2018 NFL season hit yet another gear in Sunday's 38-27 victory.

With his third touchdown throw against the 49ers — a 12-yard shot to Sammy Watkins in the second quarter — in his first regular-season start at Arrowhead Stadium, the Chiefs’ young star broke Peyton Manning’s record for most TD passes through his team’s first three games with his 13th.

Mahomes, who turned 23 last week, had already become the first player to fire 10 TDs in the first two weeks as well as the youngest ever with six in a game.

Only in his second season, Mahomes began Sunday on pace to throw 80 TDs ... a figure that dipped to 69 by day's end after he was shut out in the second half. He completed 24 of 38 passes for 314 yards.

Manning hit for a single-season record 55 TDs in 2013, the year he posted 12 through three games.

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