Dilfer took over for Alex Smith on Sunday against the Seattle Seahawks after San Francisco's starter was injured on the game's third play from scrimmage. Smith has a separated right shoulder, the extent of which will not be known until Smith has a Magnetic Resonance Imaging exam and doctors examine the X-rays that were taken after Smith was hurt early in the 49ers' dreary 23-3 loss.
It's possible the injury could be serious, and Smith could miss extended time. If it's a torn labrum in Smith's throwing shoulder, he may need surgery and could be out for the season. In any event, Smith was listed as doubtful for next week's game against the Ravens and is virtually certain not to play.
Enter Dilfer, a 14-year veteran who led the Ravens to a Super Bowl victory after the 2000 season during his only season with the team.
Dilfer, who has started for four NFL teams, hardly looked super on Sunday when he entered in place of Smith to get his first regular-season action behind center since 2005 with the Cleveland Browns.
With poor protection by the line in front of him, Dilfer completed only 12 of 33 passes for 128 yards while throwing two costly interceptions. He was sacked five times and didn't get the 49ers close to the Seattle end zone.
But this is the reason Mike Nolan brought in Dilfer, to be available if something were to happen to Smith, and he's now The Guy for the 49ers behind center until further notice.
Nolan was asked after Sunday's wipeout by the Seahawks if his team could win with Dilfer at quarterback.
"Sure, I don't have any lack of confidence in that," he replied. "This team has to play well as an entire football team for us to win. That's how we're built."
OK. So, are you ready Mr. Dilfer?
"I don't know where this thing is going to go, but when I got into work tomorrow, I will be prepared to play as long as they call on me to play," Dilfer said.
Dilfer, who has been a great mentor for Smith since he joined the team in May of 2006, watched from the San Francisco sideline every play last season when Smith became the first quarterback in the team's 61-year history to take every offensive snap in a season.
He had mixed emotions at first when he saw Smith go down on San Francisco's first offensive series.
"It's hard, because it's like seeing your little brother go down," Dilfer said. "I feel badly for him, but at the same time there is no time for sympathy in this league. I have approached this deal every time I have been in a backup situation – like I'm the starter, so if I'm called upon to play, I have the mental reps built up and I have a mindset to play long periods of time."
Dilfer couldn't get the offense going Sunday in a huge game for the 49ers, but he didn't get much help from the players around him. The offensive line committed seven penalties, and running back Frank Gore fumbled on each of Dilfer's first two series in the game, losing the first one.
Dilfer's performance, "Certainly wasn't good enough for us to win the game," Nolan said. "But I don't lack confidence in Trent. He is an outstanding leader. The only work backup quarterbacks get in preparation for a football game is the show team defense. The starting quarterback takes all the work. So, for him to go in cold turkey is a difficult job for anyone to have. Unless all the starting roles around you have done their job, it's going to make it that much more difficult. I wouldn't put what happened today on Trent's shoulders entirely."
Dilfer's presence at quarterback changes what the 49ers can do on offense. He is not nearly as mobile as Smith, who might have been able to escape a few of the sacks that Dilfer absorbed Sunday.
As Seattle linebacker Leroy Hill said, "It's a different element (with Dilfer in the game). Smith can run with the ball, so you can't send that many guys at him because he'll take off and hurt you that way. But with Dilfer, he's more of a pocket passer so we were able to blitz some more."
At this stage of their careers, Dilfer might have better touch on his passes that Smith, though that didn't show much on Sunday. To be sure, Dilfer has a huge edge in experience and has proved he can be a winner. But Dilfer had only a lukewarm 71.3 career passer rating entering the game.
That rating dropped a percentage point or two after Sunday's stinker, when Dilfer's rating was a horrible 23.3
"Trent already has a stronger personality (than Smith), he's been to the Super Bowl and he's won it," said 49ers receiver Darrell Jackson, who hooked up with Dilfer for three catches and 42 yards receiving in the loss. "He's a little older. But I think Alex has control of the huddle, the team. He's learning as we go along. But we'll be all right with Trent."
The 49ers sure hope so, because right now he's option 1-A.
"Trent is a veteran. He's been there," Gore said. "I just need to get a better feel for him. All the guys will have a chance to play with him in practice. Next week, we will get a real good feel for Trent."
Said defensive end Marques Douglas, "Oh yeah, (Dilfer) can win. He's the Super Bowl guy. All he needs to do is do his job. He's a natural leader and we can win with Trent."
The 49ers' hopes the remainder of the season may depend on it.
Can the 49ers win with Trent Dilfer at QB?
Niners Digest Top Stories
Week 2: Fantasy Football Deep SleepersFantasy Football Expert Jack Delaney reveals some under-the-radar players that could help you gain an edge in your Week 2 matchup.
2016 Expert Sleepers, Busts & BreakoutsThe best high-stakes Fantasy Football Experts and world's highest-ranked fantasy players have contributed to what we call Preseason Pro. A collection of hand-picked fantasy…
Top 10 NFL Celebration FailsRevisiting some of the worst celebration fails in NFL history.
Scout NFL Network08/24/2016
10 greatest one-handed catches in NFL historyCheck out the most jaw-dropping, awe-inspiring one-handed catches of all-time in the NFL. Find out who comes in after Odell Beckham's catch against the Dallas Cowboys.