Alli made his first League start since the opening day of the season and created the winning goal as Spurs beat Fulham 1-0 at Craven Cottage on Thursday night to move five points from the top four with a game in hand.
The 24-year-old was keen to join Paris Saint-Germain on loan in the transfer window but Spurs blocked a move, and Dele has since returned to the first-team picture following a heart-to-heart talk with manager Jose Mourinho.
"As a team-mate, he's always been professional, he put his disappointment on the side and from day one in the second part of the season, after the transfer market closed, he switched on and he started to step by step improve his fitness and get as much confidence as he can," Lloris told the London Evening Standard.
"Now he's coming back and that's good for the team and obviously the best for his season is ahead of us."
Lloris added: "We still believe we can finish high in the table, we're still in the race.
"But it's difficult obviously. We've missed points but with 12 games to go anything is possible and we need to believe. The confidence is coming back into the team, so that's very important.
"And obviously you see important players coming back, like Dele and Gareth again. For different reasons they could not play at the level they wanted to help the team [previously] but it was the case yesterday and that's good for the team and for the club."