The two most impactful quarterbacks of 2017 both ended their seasons on the sidelines with torn ACLs. Deshaun Watson and Carson Wentz put together highlight-reel campaigns before being struck down with knee injuries.

Watson's injury came in practice after six starts, while Wentz's season ended as he was attempting to scramble for a touchdown against the Rams in December. Their injuries were not the same -- Watson's was strictly an ACL tear, while Wentz also tore his LCL and had damage to his IT band -- but the stories are similar enough: Young quarterback emerges as a superstar only to suffer a serious knee injury.

Thankfully, both are progressing through their rehab processes. Watson has made his way back to the field during the preseason, and while Wentz is still a question mark for Week 1, the Eagles shouldn't need to rush him back, with Super Bowl MVP Nick Foles available in reserve. Both Watson and Wentz should have bright futures and long careers ahead.

We can't predict exactly how Watson and Wentz will recover from their knee injuries, but what we can do is take a closer look at how they performed in 2017 to infer what they'll do on the field in 2018. There are plenty of reasons to be optimistic about both of these stars, but there are also elements of their games that are unlikely to pop up again -- both good and bad. Let's start with Wentz (and if you want to skip ahead to Watson, click here).

What we saw from Carson Wentz

Wentz was the favorite to take home MVP before he suffered that knee injury against the Rams, as the former second overall pick had thrown a league-leading 33 touchdown passes and had an NFL-best touchdown-to-interception ratio of 33-7. Wentz was fifth in passer rating, but his 75.9 Total QBR was tops among quarterbacks who were eligible for the passing title. Wentz's Eagles were 11-2, tied with the Steelers for the best record in football.

Maybe you preferred Tom Brady. That's fine. At the time he went down, though, Wentz had graduated from an inconsistent rookie season into a legitimate superstar passer in Year 2.

Even if Wentz hadn't torn up his knee, I think he would have struggled to maintain that level of play in 2018. He is still going to be a very good quarterback, but there were some elements of his game from a year ago that will be tough for him to recreate, no matter how good he gets. Wentz stood out by ...

Carson Wentz's interception rate dropped despite his deep-ball rate rising, something that usually doesn't happen. Larry W. Smith/EPA

Moving the chains (and more) on third down

He was an absolute monster on third down in 2017. Wentz finished the season with a 123.7 passer rating on third down, which topped the league by a full 13 points. His 90.5 Total QBR in those same situations was 19 points better than anybody else's. Wentz racked up 9.5 yards per attempt on third-down passes, more than a full yard ahead of anyone else. You get the idea.

If we go back through recent history, his numbers still stand out. We have Total QBR numbers back through 2007, and Wentz's third-down mark was the ninth-best in that time frame. Look at the top 20 in that category, and you'll find multiple seasons from Brady, Peyton Manning, Aaron Rodgers and Drew Brees. It's the sort of company in which you would expect to see a franchise quarterback such as Wentz.

Very few of them, though, could keep up their third-down performance on an annual basis. During those top-20 seasons, our dominant third-down quarterbacks posted an average Total QBR of 88.3. The following season, those same passers were able to muster an average Total QBR of only 58.4, far closer to league average. (This excludes players who didn't play a significant number of snaps the following year due to injury.) Just one of the quarterbacks -- Manning between 2008 and 2009 -- improved on his mark from the prior year.

The same is true for passer rating. Taking the top 20 passers since 2001, we find that their average passer rating on third down during their chain-moving campaigns was 118.6. During the following season, that mark fell to an average of 90.2. Just four of the 20 quarterbacks topped a passer rating of 100 on third down the following season. To put that in context, the league average for passer rating on third down in that time frame was 83.0.

The Eagles should feel the impact of Wentz regressing toward the mean on third down. Football Outsiders has noted for years how offenses that raise their game on third down struggle to keep it up for multiple seasons, and that was the case for the Eagles in 2017. As the Football Outsiders Almanac notes, the Eagles' offense was 13th in DVOA on first down and 20th on second down before leading the league on third down. At the time of Wentz's injury, the Eagles were converting 45.3 percent of their third downs, which would have been the third-best mark in football over a season.

Wentz's injury might impact Philadelphia's effectiveness on fourth down too. You probably remember the "Philly Special," but even before the playoffs, the Eagles went 15-of-21 on fourth down last season. Their 71.4 percent conversion rate was third best in the league, and Wentz played an enormous role in that success. He ran for a league-high seven conversions in seven tries on fourth down.

Will coach Doug Pederson be as aggressive in putting his quarterback's body at risk on fourth down? And if not, will teams be able to create turnovers by stopping the Eagles on fourth-and-short?

Dominating in the red zone

Wentz was devastating when defenses were backed up against their own goal lines. He threw 22 red zone touchdown passes -- without a pick -- and took zero sacks. His 96.7 Total QBR and 116.0 passer rating were best in the league among qualifying passers through Week 14. This after a rookie season in which Wentz posted a 35.8 Total QBR in the red zone, which was 27th in the league. His passer rating of 90.0 was better, but it pushed Wentz to only 21st in the league alongside Trevor Siemian.

When Wentz went down, the Eagles were averaging 5.46 points per trip to the red zone. (These numbers count field goals as worth three points and touchdowns worth 6.95 points.) That was the best mark in football, though Philadelphia dropped to 5.20 points per trip after Wentz was replaced by an initially ineffective Foles. The Jaguars were the only team to top Pederson's offense, with Blake Bortles & Co. averaging 5.35 points per excursion into the red zone.

Regardless of whether you use 5.46 or 5.20 as the Eagles' baseline for 2017, it's tough to stay that effective in the red zone. From 2001 to '16, 98 teams averaged five points or more per trip inside the 20. The following season, just 29 of those 98 teams were able to keep their inside-the-20 success going. The list includes four Manning-era Colts teams and eight Brady-led Patriots teams, though there's only two Rodgers seasons and nary a back-to-back appearance from the likes of Brees, Ben Roethlisberger or Russell Wilson.

Those 98 offenses declined by an average of just under a half-point per drive in the red zone. On the whole, the offenses lost an average of 39 points from the previous season, and they won an average of one fewer game than they did the prior season. The Eagles might be slightly less sensitive to a red zone decline on offense because their defense is so good, but it would be an impressive feat if Wentz could do as much in the red zone as he did last season before getting hurt.

Carson Wentz's running last season helped make him deadly in the red zone. Will he run less due to his surgically repaired knee, and will that make him less effective? Robin Alam/Icon Sportswire

Cutting back on interceptions

As a rookie, Wentz threw interceptions on a respectable 2.3 percent of his passes. That's good for a debuting passer, but it's not quite as impressive when you consider that Wentz's average pass traveled only 7.3 yards in the air, which was 26th in the league. Shorter passes are less likely to be intercepted than deeper throws, which was true for Wentz. While just 15.6 percent of his throws were "deep" passes traveling 16 or more yards downfield, those passes accounted for seven of his 14 picks.

The Eagles took the training wheels off Wentz last season and let him chuck it downfield. His average pass went 9.8 yards in the air, the second-highest mark in the league behind that of Jameis Winston. Typically, we'd associate that with more interceptions, but Wentz actually reduced his interception rate. He was picked off on only 1.6 percent of his pass attempts, the eighth-best mark in the league.

It's incredibly tough to throw deep that frequently without getting picked off at even a league-average rate. Going back through 2007, there have been 18 players whose average pass attempts traveled between 9.5 and 10 yards in the air, including Wentz. The other 17 passers in this group combined to post an interception rate of 3.1 percent, nearly double Wentz's mark. (If we expand the group to a larger sample and include passers whose average throw was between 9 and 10 yards, the interception rate remains 3.1 percent.)

Wentz's 1.6 percent interception rate is tough for any quarterback to keep up, let alone a passer picking up chunks of yardage like Wentz. The signal-callers who have kept their interception rates this low are either relatively conservative quarterbacks (Brady, Alex Smith) or passers who sacrifice interceptions but have higher-than-average sack rates (Tyrod Taylor). Wentz does not yet fit into either category.

Football Outsiders also notes that Wentz had six dropped interceptions last season. When you add those in for every passer and remove the interceptions on Hail Mary attempts and tipped or dropped passes, Wentz's 2.8 percent adjusted interception rate is tied for 14th in the league alongside that of Eli Manning.