With the announcement this week that Spider-Man officially joins the Marvel Cinematic Universe, Andrew Garfield will be soon be replaced as our Friendly Neighborhood Spider-Man for the upcoming Captain America: Civil War, as well as the solo feature film aimed for a 2017 release. This obviously wouldn't be the first time that the role was handed off to another star for another set of movies. It's just a shame that Garfield has been notably one of the highlights of the recent reboot, but essentially he's being brought down to a Brandon Routh level of treatment (there's always the chance of being in Agents of S.H.I.E.L.D., Andrew).
There was a time though that Tobey Maguire almost didn't make it for Spider-Man 2 due to injuries. It's a pretty well known fact that Jake Gyllenhaal was practically on speed dial should Maguire not be able to continue. Maguire had hurt his back filming Seabiscuit and things were looking pretty bleak for him to continue. Reports were saying that Gyllenhaal was in the middle of preparing for the role when Maguire made a speedier recovery than expected. Gyllenhaal was already dating the franchise's Mary Jane Watson, Kirsten Dunst, at the time, so their chemistry would have been palpable for sure and potentially better than what Maguire's Peter and her MJ had going on.
Maguire was always going to be Sam Raimi's first choice, with all the lengths he had to go to prove he would "the one", but it would have been an interesting move for Gyllenhaal to take the reins. Take into consider that Maguire was just made a household name with the first movie as it was his first blockbuster (he was mainly known for his indie hits like Wonder Boys, Pleasantville, and The Cider House Rules at the time) and to replace him so quickly for a budding franchise (and the fact that Maguire had already signed on for a trilogy). By comparison, Gyllenhaal had only remedial success with the cult classic Donnie Darko, but also the bomb Bubble Boy around the same time, but his star was definitely on the rise. Something like Spider-Man 2 would have catapaulted him even faster.
Things worked out for Gyllenhaal for the best, though. With the Spider-Man 2 schedule nullified, he was able to star in Brokeback Mountain, which earned him an Oscar nomination. Maguire worked through the pain and ordeal to help make Spider-Man 2 one of the highest grossing movies in 2004, and continued to make Spider-Man 3, ending the first trilogy. Thirteen years later it's still one of the biggest cases of comic book cinema what if…?