In the end zone, Stephon Gilmore intercepted Russell Wilson's throw intended for Courtland Sutton to seal a 12-9 overtime victory.
Four minutes and ten seconds into the first overtime in NFL history, McLaughlin completed a pass of 47 yards, putting the Colts (2-2-1) ahead.
The Broncos (2-3) passed up a chance at tying the game with a chip-shot field goal by Brandon McManus or maybe getting a first down.
While Matt Ryan threw two interceptions into the hands of safety Caden Sterns and, he still managed to grind out the victory.
Gilmore intercepted Wilson's throw to Jerry Jeudy in the end zone on third-and-4 from the 13 with 5 seconds left in regulation.
Many fans wondered if this game would be one of retribution (Phillip Lindsay coming to his hometown to upset the Broncos).
McManus kicked field goals from 33 and 44 yards, and McLaughlin kicked a 52-yarder with 12 seconds remaining in the first half.
Both the Colts (14.3 ppg) and the Broncos (16.5 ppg) began the game with the lowest scoring averages of Ryan (16 yrs.) and Wilson (11).
On Sunday, October 16, the Colts will host the Jacksonville Jaguars, while on Monday, October 17, the Broncos will travel to take on the Los Angeles Chargers.