Fantasy Alert: Matthew Stafford Out vs. Packers with Injury, Rypien Named Rams' QB1

Los Angeles Rams quarterback Matt Stafford will not start Sunday's game against the Green Bay Packers because of a UCL sprain, per NFL Network's Ian Rapoport.

Brett Rypien will start under center for Los Angeles.

Stafford suffered the UCL sprain in his right thumb during his team's 43-20 loss at the Dallas Cowboys last Sunday. Rypien took over down the stretch.

Rams head coach Sean McVay told reporters the next day that Stafford was "day-to-day." Stafford did not practice on Wednesday due to the ailment in the lead-in to the matchup against the Packers.

Rypien completed 5-of-10 passes for 42 yards in Stafford's place versus Dallas.

The 27-year-old is in his fourth NFL season after spending three years with the Denver Broncos. For his career, the ex-Boise State star has completed 85-of-140 passes (60.7 percent) for 820 yards, four touchdowns and eight interceptions in nine games.

With Rams rookie Stetson Bennett still on the Reserve/NFI list, L.A. signed a third quarterback in Dresser Winn to its practice squad.

Winn signed with the Rams as an undrafted free agent out of the University of Tennessee-Martin and stuck with the team through training camp before being cut.

The rookie completed 232-of-379 passes (61.2 percent) for 2,928 yards and 18 touchdowns (11 interceptions) during his final collegiate season.