Ravens fans have waited four weeks for some definitive word on when starting quarterback Joe Flacco will be back on the field, but they saw first-hand on Saturday night that things could always be worse.

Former Ravens quarterback Tyrod Taylor was just minutes into his personal dress rehearsal for the Buffalo Bills’ season-opener when he suffered a concussion at M&T Bank Stadium, where he spent four seasons as Flacco’s understudy.

He was sacked deep in Bills territory on his second possession of the game and his helmet slammed into the turf, throwing into doubt whether he’ll be ready to start the season on time.

The injury will have no impact on the Ravens, but it should provide a reality check for anyone who thinks that everything will be just fine as soon as Flacco returns to practice to prepare for the opener against the Cincinnati Bengals.

The quarterback situation will always be tenuous, because that’s the brutal nature of football.

Flacco is expected to begin practicing soon, but he — and the Ravens — will still be one false move or freak hit away from Ryan Mallett taking over as starting quarterback for an extended period.

That’s why you can’t dismiss Mallett’s three unimpressive preseason performances and simply look ahead to Flacco’s return on Sept. 10. Regardless of what the Ravens announce, Flacco is still not a lock to play that day and is certainly no lock to play well after missing training camp and the preseason.

Nevertheless, coach John Harbaugh explicitly promised after the game that Flacco will play in the season opener, but bristled at a question about when his franchise quarterback will practice for the first time. Not sure why that’s such a sensitive subject, but my future is never going to depend on the performance of Ryan Mallett.

Flacco hasn’t had one training camp rep with new receiver Jeremy Maclin or veteran all-purpose running back Danny Woodhead. He, like everybody else, doesn’t know what the patchwork offensive line is going to look like in two weeks.

Mallett played little more than a quarter on Saturday night, completing 6 of 10 passes for 58 yards before he was replaced by third-string QB Josh Woodrum.

That was almost certainly by design, since Mallett didn’t do anything unforgivable during three unproductive possessions, but he also didn’t do enough right to engender confidence that he will be able to move the offense against a pretty good Bengals defense if he ends up being the starter in Game 1.

The early arrival of Woodrum could be interpreted a number of ways. He had played very well in the first two preseason games, but it’s always difficult to evaluate a young quarterback who generally plays in the preseason against second and third-string defenses.

That was certainly the case in his appearances against the Redskins and the Dolphins, but he played so well and the offense looked so dramatically different than the one Mallett was running in the first halves that the Ravens needed to get a look at Woodrum against a higher level of competition.

It’s also possible that Harbaugh simply didn’t want Mallett on the field any longer than necessary, and the injury to Taylor validated that decision after the fact.

Harbaugh is never going to admit that his quarterback situation is that fragile, but until Flacco is back on the field both healthy and effective, there is every reason to err very much on the side of caution with his most viable veteran quarterback.

Really, what choice does he have?

No doubt, there are some fans who watched the first two games and wondered why Woodrum wasn’t behind center for the first offensive series of Saturday night’s game, but that’s just not the way things work at this level.

Woodrum got his chance to back up his performance from the first two games and suddenly was reincarnated as a small-school quarterback. He’ll get another extended look next week, but that probably isn’t going to change anything because the quality of the competition will again be questionable.

Former Ravens coach Brian Billick has a saying about getting too excited about over-achieving players during the preseason: “Never fall in love with a guy in shorts.”

The point being that pedigree matters and Mallett, in spite of his mediocre performance in his three preseason starts, has a track record and the rookie from Liberty University does not.

The Ravens appear to have put together a dominating defense, so — in the possible absence of Flacco — they would not be desperate for someone to come in and put 30 points on the board every Sunday.

In that situation, what they would need is someone who can manage the game, minimize mistakes and handle the pressure that comes with being a starting quarterback in the NFL. Unfortunately, Trent Dilfer is not available.

For better or worse, that guy is Mallett, but it certainly isn’t a comforting thought.

peter.schmuck@baltsun.com

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