The 22-year-old winger joined Hibs last summer but failed to establish himself in Lee Johnson’s squad and made only nine appearances in all competitions.
Tavares failed to get into former Hibs boss Johnson’s first-team early this season, but Montgomery put him in the starting line-up.
McManus is impressed with Tavares’ displays in recent games and admitted that after the Portuguese’s poor first season at Easter Road, he expected the winger to leave this summer.
The ex-Hibs attacker says that Montgomery believes in Tavares and added that the player has gone through massive change under the new Hibernian boss.
“The transformation in Jair Tavares under Nick Montgomery has been remarkable and his goal up in Tayside was wonderful”, McManus wrote in his Daily Record column.
“I’ll be honest, I thought he’d have been away in the summer.
“He arrived with a big reputation and a four-year deal but I saw nothing that suggested he’d be worth that last season.
“He was in Siberia.
“Training with the development team and not even in the first team changing room.
“I’ve been in that situation myself being completely bombed out by a manager and to be brutally honest you can only pray he gets the bump.
“That’s what opened the Easter Road door again for Tavares and boy has he taken the chance.
“It’s amazing what a change in manager can do.
“Montgomery clearly believes in him and his Portuguese assistant Sergio Raimundo will help him feel comfortable.”
Tavares has featured nine times in the league under Montgomery this season and has found the back of the net on two occasions.