Logan Wilson intercepted Matthew Stafford twice and the Bengals (1-2) recorded six sacks to hold Los Angeles' offense at bay.
The Rams (1-2) were held to three field goals from Brett Maher before Stafford found Tutu Atwell for a 1-yard TD with 1:03 left in the game.
Four plays into Los Angeles' first drive, Atwell took an end around and raced to the end zone from 24 yards out.
Both kickers traded field goals later in the quarter, with McPherson's 53-yarder as time expired in the first half sending the teams into the break tied at 6-6.
McPherson added two more field goals to push Cincinnati's advantage to 10 before Stafford connected with Atwell for the late score that gave Los Angeles a fighting chance.
Persons:
Joe Burrow, Ja'Marr Chase, Logan Wilson, Matthew Stafford, Brett Maher, Stafford, Tutu Atwell, Evan McPherson, Atwell, DJ Reader, Maher, McPherson, Joe Mixon, Mixon
Organizations:
Cincinnati Bengals, Los Angeles Rams, Bengals, Stafford, Rams, DJ, Cincinnati, Thomson
Locations:
Los Angeles, Cincinnati