Following consultation with the Los Angeles Rams medical personnel, Matthew Stafford entered concussion protocol. The Rams placed Stafford in the protocol following the customary regular round of post-match health assessments.Thursday marked Stafford's third day in the concussion protocol, and he sat out yet another session. The Rams will start backup quarterback John Wolford if Stafford cannot start this week's game against the Arizona Cardinals.Adam Schefter@AdamSchefterNo Matthew Stafford at practice for a second straight day.2229130No Matthew Stafford at practice for a second straight day.Sean McVay said the team wouldn't rush Stafford back as player safety takes priority. The L.A. Rams have been defeated in four of their last five games and are desperate for a win against the Cardinals. The defending Super Bowl champions have had a poor start to the 2022 season. At 3-5, they are three wins behind the Seattle Seahawks in first place.According to Sean McVay, Matthew Stafford's symptoms began after the team's Week 9 loss to the Tampa Bay Buccaneers. Team doctors determined that Stafford was required to join the protocol following a series of post-game tests. Stafford's ailments were not obvious during the match.Ian Rapoport@RapSheetPotentially significant: #Rams QB Matthew Stafford is in the NFL's concussion protocol, coach Sean McVay announced.3397296Potentially significant: #Rams QB Matthew Stafford is in the NFL's concussion protocol, coach Sean McVay announced.Stafford was hit eight times in the Rams' defeat against the Tampa Bay Buccaneers and sacked on four occasions.Matthew Stafford ruled out of Week 10 matchup against the Arizona CardinalsSean McVay was confident that Stafford could clear the protocol in time for Sunday's game against the Arizona Cardinals. However, close to kick-off, the Rams ruled Stafford out of the game.Sports Illustrated@SInowCardinals’ QB Kyler Murray and Rams' QB Matthew Stafford are both inactive today We will see John Wolford vs. Colt McCoy at 4:25pm5712Cardinals’ QB Kyler Murray and Rams' QB Matthew Stafford are both inactive today We will see John Wolford vs. Colt McCoy at 4:25pm https://t.co/WPHRoKQdzUIn the last 12 years, Stafford has only missed eight games, all of which occurred in 2019 with Detroit due to a midseason back issue. While there is time for Matthew Stafford to recover in time to face Arizona, it is very much a coin toss at this time.Rams backup quarterback John Wolford will start under center and Bryce Perkins will be his backup. It will be interesting to see how Wolford does in this huge matchup against the Cardinals.