It wasn't always this way, of course. Last season, right after he threw a 75-yard touchdown pass to Dwayne Bowe, Cassel was drawing comparisons to Trent Green. But his last five games – 123 yards per game, 4.6 yards per attempt, three touchdowns, 10 interceptions and a 43.8 quarterback rating – are basically the worst stretch of his career and the Chiefs still have yet to play the toughest part of their schedule.
This is not a picture of an ascending player. Fans, as ignorant and reactionary as they can often be, are not blind. The majority have had enough.
That majority hit an all-time high after Sunday's game-ending debacle in San Diego where Cassel, attempting to throw a screen pass to Dexter McCluster, inexplicably drilled Chargers safety Eric Weddle right in the belly with a perfectly thrown ball.
This came after a brilliant defensive stand by Kansas City's defense and a 23-yard strike from Cassel to tight end Leonard Pope, giving hope that the Chiefs might win their first game of the season. But if you've followed Cassel's career at all, you should know by now that there is no hope in such a situation.
That's because quite literally, Cassel has never won a game when his team is trailing by seven or less in the fourth quarter with two minutes or less on the clock. Not one time in seven NFL seasons, 63 games and 48 starts. Not in New England, not in Kansas City and, the way it's looking, not on planet Earth.
Cassel has been in such a situation nine times now, and always comes up the loser.
It happened in his first start with the Chiefs. At the conclusion of that game, trailing the Oakland Raiders by three points with one minute, seven seconds remaining, Cassel never even came close to driving the Chiefs into tying field-goal range. The offense gained all of six yards before giving the ball up on downs.
Thirty-two games later, it appears nothing has changed, and that's why fans are ready to run Cassel right out of Kansas City on the same train that rid them of Steve Bono and Elvis Grbac. Coincidentally, Bono and Grbac also hoodwinked Chiefs general managers into acquiring them after backing up future Hall of Famers.
What heroic feats has Cassel performed in the clutch as a Chief? Let's review.
Week 2, 2009 – Raiders 13, Chiefs 10
With only one timeout remaining and needing 50 yards to get into field goal range, Cassel dumps the ball short to Dantrell Savage for nine yards. Two snaps later he takes a sack on third-and-one.
Embarrassing anecdote: JaMarcus Russell wins the game with his own clutch drive.
Cassel's first game with the Chiefs ended like his last game with the Chiefs.
After moving the Chiefs to within 21 yards of the tying score, Cassel completes two passes for no yards before throwing an eventual interception. Later, given one last chance for a desperation drive, he dumps the ball in the middle of the field for seven yards despite not having a timeout.
Embarrassing anecdote: Cassel later claims he made no mental errors despite throwing four interceptions.
Week 15, 2009 – Browns 41, Chiefs 34
Attempting another desperation drive with no timeouts, Cassel throws the ball in the middle of the field for seven yards. Later, he attempts a Hail Mary from the 26-yard line, quite possibly the first Hail-Mary pass thrown that close to the goal line in NFL history.
Embarrassing anecdote: The Hail Mary doinks off the crossbar like a field goal.
Week 17, 2009 – Bengals 17, Chiefs 10
With two minutes remaining in the Chiefs' season, Cassel drives the Chiefs to midfield before promptly throwing an interception.
Week 6, 2010 – Texans 35, Chiefs 31
Attempting to throw a Hail Mary, Cassel is sacked for a 12-yard loss.
There's plenty more evidence to go around, of course. It would be easy to point out last year's Raiders game, when Cassel completely failed to mount any sort of attempt at a game-winning drive in overtime. There's also the fact that despite his deceptive statistical success from a year ago, Cassel's performance when the Chiefs trailed by seven or fewer points (85 attempts, 52.9 percent completions, three touchdowns, four interceptions, 63.7 rating) was abysmal.
To be fair to Cassel, he hasn't completely failed in late-game situations. He has, at times, directed game-tying drives, such as the one he punctuated with a 16-yard scoring strike to Dwayne Bowe in 2009 against the Dallas Cowboys.
But does anyone really remember, let alone praise, quarterbacks for game-tying drives? When Chiefs fans reminisce about Joe Montana's 1994 Monday Night Football comeback victory over John Elway, do you think they care that Elway scored with 1:29 left? Not in the least.
No one cares about Cassel's "comeback" against the Cowboys in 2009, either. Because he failed in overtime that day, twice. Just as he failed Sunday in San Diego. In a close game, Cassel is a ticking time bomb waiting to explode and blow everything.
The bottom line: late in the game, with his team on the wrong end of the scoreboard, Cassel has never shown an ability to go out and win. This weekend's game against the Vikings will be his 49th start. Win or lose, most Chiefs fans will not care if he leaves Kansas City after it's over.
Because you know he's not coming back.