The Eagles' season changed forever on Dec. 10. If that sounds a tad dramatic, it is. That was the day the team lost second-year quarterback Carson Wentz, who suffered a torn ACL in the Week 14 matchup against the Rams. The Eagles entered the game with a 10-2 record, were arguably the NFL's best team and Wentz was probably headed for the MVP award.

A trip to the Super Bowl -- their first since the 2004 season -- was a legitimate reality.

And then Wentz was sandwiched by two Rams defenders while diving into the end zone on a play that would be overturned:

Wentz remained in the game for several more plays and even threw a touchdown pass before heading for the locker room. He later had an MRI, with a diagnosis of a torn ACL and months of recovery to follow.

Wentz's MVP season ended at the Coliseum that afternoon but not before he set the team record for touchdown passes, tossing his 32nd and 33rd against the Rams. He had just seven interceptions and ranked eighth among all quarterbacks in total value (behind Matt Ryan and ahead of Alex Smith), according to Football Outsiders' metrics, even though he missed the final three regular-season games. In terms of value per play, Wentz was even better; he ranked fifth, behind only Case Keenum, Tom Brady, Drew Brees and Philip Rivers.

It was easy to understand why Eagles fans thought the Super Bowl went from destiny to pipe dream in the time it took Wentz to limp off the field.

Enter Nick Foles, who replaced Wentz at quarterback in Los Angeles. In limited duty he was a tidy 6 of 10 for 42 yards, and didn't commit a turnover. It was enough to help the Eagles beat the Rams, 43-35, and in the process, clinch the NFC East title.

No one will ever mistake Foles for Wentz. The young franchise quarterback is often mistaken for British royalty.

Meanwhile, the wily veteran draws comparisons to...

But don't be fooled by the nerdy appearance and the far-off gaze. Foles can play. Like most people, we weren't convinced of this as recently as two weeks ago because he looked very much like a backup quarterback who hadn't seen meaningful minutes in a couple years.

In Foles' last two regular-season starts as Wentz's replacement, he was 23 of 49 for 202 yards, with a touchdown, two interceptions and a passer rating of 48.2. For the season, Foles appeared in seven games and threw five touchdowns and two picks but his 79.5 passer rating seemed to better reflect who he was. That was confirmed by Football Outsiders' value-per-play metric. Among quarterbacks attempting fewer than 200 passes during the regular season, Foles ranked 15th out of 26. He was between Mike Glennon and Bryce Petty. Put another way: Foles wasn't even a replacement-level quarterback, which went a long way in explaining why the Eagles were home underdogs in both of their playoff games.

But here's the thing: This is also the same Nick Foles who in 2013, during his first stint with the Eagles, started 10 games and completed 64 percent of his throws with 27 touchdowns and just two interceptions, and a passer rating of 119.2.

No one expected that Foles to show up but perhaps there was a happy medium between 2013 Foles and 2017 Foles. Anything approximating average QB play would be enough to give the Eagles a chance.

In Philly's two postseason games, here are Foles' numbers: 49 of 63 for 598 yards, 3 touchdowns, no turnovers and a passer rating of 122.1. As it turns out, Playoff Foles is better than 2013 Foles.

In the short term, this is a fantastic development for the Eagles, who have played inspired football in back-to-back weeks and will have a real chance at the Lombardi Trophy against the Patriots.

The long-term question becomes: When will Wentz be healthy enough to return to the field?

When it comes to recovering from ACL surgery, there is no straightforward answer. Typically, it can be anywhere from 9-12 months until a player is able to return to the field. But quarterbacks are different than other football players in that they spend most of their time in or near the pocket and aren't required to run, cut, plant and jump on nearly every play. But even among quarterbacks there are differences.

Philip Rivers, who actually played a playoff game after tearing his ACL, was never the mobile threat that Wentz is. It's also worth noting that Rivers' gutsy performance wasn't particularly effective (though amazing given the circumstances): 19 of 37 for 211 yards, no touchdowns, two interceptions.

This isn't a surprise since the ACL -- the anterior cruciate ligament -- stabilizes the knee. Living permanently without an ACL is a reality for many people but it would also mean an end to football player's career.

Wentz's athleticism was a big part of the Eagles' offense -- the run-pass options (RPOs), the rollouts, the scrambles. Put another way: It will take longer for Wentz to return to that style of play than it will for him to return as a "pocket passer."

Days after Wentz's injury -- but before his surgery, which was performed by Dr. James Bradley, an orthopedic knee specialist based in Pittsburgh who also serves as the Steelers' team doctor -- ESPN's Chris Mortensen spoke with another noted orthopedic specialist, Dr. James Andrews, who spoke in general terms about ACL recoveries.

"[Bradley] told me ... that expectation should be tempered for a player with an ACL surgery to return by start of '18 season," Mortensen tweeted. "He says ACL repairs need 9-to-12 months."

We can all agree that Adrian Peterson is a freak. Even more freakish is that he started in Week 1 of the 2012 season, nine months after his injury, started 15 more games, and finished with 2,097 rushing yards and 12 touchdowns.

But there is only one Adrian Peterson.

There have been other, less successful examples of players returning too soon; Robert Griffin III tore his ACL during a January 2013 playoff game. He missed the following training camp and preseason, but started Week 1 of the regular season and was never the same quarterback we saw as a rookie.

But there are success stories too; Tom Brady (torn ACL, September 2008) is, well, Tom Brady. Carson Palmer tore his ACL in November 2014, returned to play all 16 games in 2015 and threw for 4,671 yards with 35 touchdowns, 11 interceptions and a 104.6 passer rating.

The point: If a player doesn't rush rehab, they return to their pre-injury form. So what are the realistic expectations for Wentz?

"I think he could do well enough to participate in limited fashion in throwing as early as [late May, early June] offseason programs," Dr. David Chao, an orthopedic surgeon, told the San Diego Union-Tribune shortly after Wentz's injury. "I think he'll be able to throw well before training camp.

But when will he be game ready? I think he has a chance to be game ready as more of a pocket quarterback come the first week of the season. But if you want him to be run-pass-option guy and be himself, look for midseason for maybe even a little bit longer."

Here's Wentz last week, moving pretty well a month out from surgery:

In case you're wondering, Foles is signed through the 2018 season and his $7.6 million cap hit suddenly seems like a ridiculous bargain.