He initially considered leaving, but stuck it out despite spending most of his time on the sideline, watching instead of playing.
The patience paid off.
With Kelly out at least one game with a foot injury - maybe more - Bercovici finally gets his chance to lead the 15th-ranked Sun Devils.
''I've been ready for this for a long time,'' Bercovici said. ''I really do put the pressure and the constraint on myself that this is an opportunity I owe to my teammates. If I wasn't ready right now, it would be pretty obvious to the guys at practice. I think the guys felt confidence in me after this practice knowing there's no drop-off.''
Kelly has been Arizona State's starter since winning a tight battle with Bercovici and Michael Eubank in 2012. He's been one of the best quarterbacks in program history, leading the Sun Devils to a pair of bowl games while dotting his name across the school record book.
But now Kelly is out. He hurt his right foot against Colorado on Saturday and left the stadium on crutches and wearing a protective boot.
Kelly will not play in the Sept. 25 game against No. 12 UCLA. Beyond that is a bit of a mystery; coach Todd Graham said he won't address Kelly's injury until after the next game.
Now it's Bercovici's turn and the Sun Devils aren't expecting any kind of drop-off.
''I've got all the confidence in the world,'' Graham said. ''Mike has a lot of things that he adds to the offense from a skill standpoint. The key is that we adapt what we're doing to him.''
Bercovici's best attribute is his strong arm. It also has gotten him into trouble at times, leading to interceptions when he tries to force balls into tight spaces.
Experience also could be an issue.
The junior has thrown a total of 24 passes, most of those in mop-up duty, including 17 this season. He was 2 for 4 for eight yards after Kelly was injured against Colorado last week.
Despite being mostly a practice player, Bercovici has worked as though he was the starter, conscientiously going through the game plans, sharpening his skills as he went along, waiting for his opportunity.
''Since I've been here I've done everything I can to prepare myself to run this offense,'' Bercovici said. ''All I need to do is my job. The quarterback runs this offense as in every offense, but this one more. If I make my right decisions, we're just going to keep moving the ball.''
Arizona State had no trouble moving the ball with Kelly under center.
The Sun Devils have been one of the nation's top scoring teams and offensive producers the past three seasons. Through three games this season, Arizona State is tied for 10th nationally with 47 points per game and is 19th in total offense at 539 yards.
Whether Bercovici can keep that going is clearly up in the air, particularly since the Sun Devils will take a big step up in competition against the Bruins.
The good news for Bercovici and the Sun Devils is they'll have extra time to prepare. Arizona State has a bye this week, giving Bercovici 11 days to get ready for his big shot.
''He's prepared for this moment,'' Arizona State offensive coordinator Mike Norvell said. ''I'm excited about it because I know that I have a guy that has not wasted opportunities the last two years. He's worked to get better each and every day for this opportunity should it ever present itself, and now it has on a grand stage.''