Not so much on the field — his 38-year-old legs were all but done when he retired — but the former Italy international's leadership and presence are missed by a team that has begun the Major League Soccer season with three losses and a draw.
New coach Frank Klopas' side will be looking for its first victory against another winless side — the New York Red Bulls — on Saturday at Olympic Stadium.
"Alessandro had a strong personality on the team," striker Marco Di Vaio said Thursday. "In a game like that (against New York), maybe he'll put his personality (forward) and maybe give confidence to the players.
"But we have good players, a good team. We're training a lot harder the last (few) weeks and we know that if we concentrate, we are a good team."
Di Vaio and Nesta were the Impact's statement signings during their first year in MLS in 2012. They grew up together with the Lazio club in Rome.
Nesta followed his childhood friend to Montreal without even demanding the status or salary of a designated player. But while 37-year-old Di Vaio showed he can still dominate by scoring 20 goals last season, Nesta was noticeably slower than in his prime as a four-time Serie-A defender of the year with AC Milan.
Nesta retired at the end of the 2013 campaign, after helping the Impact reach the playoffs in only their second MLS season. He stayed with the club as a technical consultant based at his home in Florida.
It's debatable whether his play would have helped pick up extra points this season, but he was someone the other players fed off both on and off the pitch.
"Even in the last couple of months of the season, he wasn't the best player on the field, but what he brought from a psychological standpoint and an energy standpoint, it was really nice to have him on the field," said goalkeeper Troy Perkins.
"Without him, it's a different team. We have different players and we're playing a different style this year. No team's going to replace Alessandro Nesta. You adapt without him."
The central defence has been one of many problem areas thus far, partly due to injuries.
Spaniard Adrian Lopez, signed last season, has yet to play since blowing out a knee after only one game. And Colombian Nelson Rivas has been hurt on and off since he joined the squad in 2012.
Klopas said Rivas, who has been running this week, should be able to return to the lineup in a week or two.
In the meantime, they are using Matteo Ferrari, another Serie-A veteran who may have lost a step, and converted right back Hassoun Camara in the middle. The outside defenders are also new, with rookie Eric Miller and former Red Bull Heath Pearce starting last Saturday's 1-1 draw in Philadelphia.
With the midfield guilty of too many turnovers, the defence has been tested too often. The team has conceded seven goals in four games, while scoring only three.
Klopas said it is a matter of time before the back line becomes a cohesive unit.
"We stress the importance of communication," said Klopas. "It's a position where, if you make a mistake, everybody sees it.
"We keep talking about making sure the decision making is good. Not taking a lot of risks in the back. But the last game, there were some good moments. It takes time to get to know each other."
Nesta played only 23 of 34 games last season and there's a good chance he would not have played Saturday even if he was still around. The Big O's artificial surface is especially hard on the legs of the older players.
"It's hard on the body," said Di Vaio. "Alessandro, last year, when he played here he needed three four days to recover from the game."