Rivers methodically moved the Chargers (3-3) on three scoring drives of at least 74 yards as he rebounded from a three-interception performance in a dismal loss at Oakland.
The Colts (4-2) blew a chance to take a two-game lead over Tennessee in the AFC South. Colts receivers had several drops, including Darrius Heyward-Bey, who couldn’t bring in a likely long touchdown pass down the right sideline in the second quarter.
Novak’s fourth field goal, from 50 yards, came with 1:55 left.
There were family ties in this one: Chargers defensive coordinator John Pagano beat older brother Chuck, the Colts’ coach.
The Colts next face Peyton Manning and the high-powered Denver Broncos on Sunday night.
It will be Manning’s first game in Indianapolis since he was released.
Linebackers Donald Butler and Jarret Johnson, and guard Chad Rinehart were among San Diego’s inactive players Monday night.
Butler has a groin injury, Johnson a hamstring injury and Rinehart an injured toe.
Inactive for the Colts were free safety LaRon Landry, running back Daniel Herron, inside linebacker Kavell Conner, lineman Khaled Holmes, tackle Xavier Nixon, outside linebacker Bjorn Werner and defensive Montori Hughes.
Johnnie Troutman started on Monday night for Chad Rinehart, Tourek Williams for Johnson and Andrew Gachkar for Butler.