Mallett would become the Ravens' fourth starting quarterback in their past six games. This comes after Joe Flacco had started 122 straight regular-season games, the NFL's fifth-longest streak for quarterbacks in NFL history.
The Ravens (4-10) signed the strong-armed Mallett 12 days ago, and the coaching staff has repeatedly praised him for his work ethic in learning the new offense. Mallett was cut by the Houston Texans in October after being late for team activities, including missing a team flight to Miami.
Mallett, 27, is considered the favorite to back up Flacco next season. Mallett can earn $2.5 million next season if certain playing time incentives are reached. There is no guaranteed money, which means he is on trial period in Baltimore. The Ravens signed him this season because they wanted to see what he could do on the field in 2015.
Ravens coach John Harbaugh said Monday that Mallett would be in the starting quarterback conversation along with Jimmy Clausen and Matt Schuab, and offensive coordinator Marc Trestman indicated Thursday that Mallett was ready to start.
"He has had enough reps that if John [Harbaugh] decides to play him, and we decide to go that way, we feel he could manage the game," Trestman said.
Mallett hasn't started a game since he was with the Texans on Oct. 8, when he left after taking a shot to the ribs and never returned. He was 1-3 as a starer this season, with three touchdowns and four interceptions for a 63.6 passer rating.
The Ravens have had a fluid quarterback situation since Flacco tore knee ligaments at the end of a Nov. 22 game against the St. Louis Rams. Schaub started the first two games without Flacco, throwing four interceptions (including two returned for touchdowns).
Clausen did an admirable job in replacing Schaub after Schaub suffered a chest injury, and Clausen remained the starter last Sunday after Schaub was healthy enough to play. In two starts, Clausen set career highs in passing yards each time but led only two touchdown drives in 22 possessions. The Ravens could bring back Clausen to compete against Mallett for the backup quarterback job next season based on what he's done in a brief period this year.
It was assumed that it was just a matter of time before Mallett became the starter, whether it was Sunday or next week's season finale in Cincinnati. Mallett has impressed Ravens officials with his dedication to learn the offense since signing with Baltimore Dec. 15, from staying long hours at the team facility to working with quarterbacks coach Marty Mornhinweg and receivers after practice.
After his first practice with the Ravens a week and a half ago, Mallett acknowledged he "acted immaturely" in Houston.
"There were reasons for it. But that's not going to be discussed right now," Mallett said. "The best thing probably was for me to be cut."
If Mallett starts Sunday, Clausen will likely be his backup. Schaub would probably go from the starting role to inactive in a matter of four weeks.
This would mark the first time in the Ravens' 20-year history that they will have started four quarterbacks in a single season. The Ravens previously started three in 1999 (Scott Mitchell, Stoney Case and Tony Banks) and 2007 (Steve McNair, Kyle Boller and Troy Smith).