And, Um, Who Should Start?

Photo: Joe Robbins/Getty Images (Tebow); G Fiume/Getty Images (Sanchez)

After Tim Tebow became Denver’s starting quarterback last season, he led his team to seven wins in its last eleven games, a divisional crown, and a first-round overtime playoff triumph against the heavily favored Pittsburgh Steelers. Mark Sanchez, meanwhile, started all sixteen Jets games, failed to get his team into the playoffs, and presided over an end-of-year locker-room meltdown. So Tebow should start, right? Not so fast. To assess the potential effectiveness of each player, we asked Aaron Schatz, creator of stat-guru website Football ­Outsiders, to break down the facts.

To measure offensive players against one another, Football Outsiders uses a rating called DVOA (defense-adjusted value over average), which factors situation and opponent into an analysis of each play in the season, then spits out a percentage by which a player exceeds or underperforms the norm at his position. Last year, Sanchez’s passing DVOA of -12.5 percent ranked him just 29th out of the 47 quarterbacks who threw 100 or more ­passes. But Tebow’s passing DVOA was even worse—an abysmal -22.7 percent, for 37th in the league. When we project what each quarterback will do over this coming season if given every one of the Jets’ snaps, the numbers tell a similar story. In our analysis, Mark Sanchez is the more accurate passer and throws for more yards, more touchdowns, and fewer interceptions per attempt (see Chart 1, above).

But Tebow’s real value lies in his running game, right? He’s a master improviser who is big, strong, hard to tackle, and can help his team win in myriad ways, isn’t he? It’s true that Chart 1 shows that Tebow would rack up many more rushing yards and touchdowns than Sanchez if he were the starter, but it’s important to look at what those numbers accomplish. Last season, Tebow gained a whopping 668 yards on the ground, but a lot of them came on third-down scrambles that didn’t manage to move the chains. Twenty-nine times, he ran on third down and didn’t get a new set of downs, including nine stat-padding runs of at least five yards. His rushing cost the Broncos—his rushing DVOA was -18.3 percent. Mark Sanchez, for his part, wasn’t quite Arian Foster, but his -8.2 percent rushing DVOA last season showed that he was actually a significantly more effective runner than his new backup. Sanchez also matched Tebow rushing touchdown for rushing touchdown, with six.

Despite all that, the Jets have suggested they plan to give Tebow around 100 snaps this season—most of them in the wildcat formation and other specialized situations. Chart 2 shows Football Outsiders’ projection of what the season will look like for the two Jets QBs under that plan. Tebow’s numbers may look positive enough, given the limited number of snaps, but this kind of quarterback time-sharing has never worked in the NFL, and our analysis shows the Jets have a better chance of success with Sanchez, not Tebow, under center. Tebow may help the Jets sell more jerseys, but that’s about it. If the Jets want to maximize their potential for wins, they’d be better off sticking with Sanchez.

And, Um, Who Should Start?