The Frenchman suffered a long-term hamstring injury in his opening weeks at the club and has since struggled for gametime since his summer move from Borussia Dortmund.
Reports in Spain have linked Dembele with a surprise move away from the club in recent weeks.
But Barcelona boss Ernesto Valverde placed his faith in the youngster during the last 16 clash with Chelsea earlier this week.
And footage has emerged of Messi helping Dembele at every possible opportunity during the game.
The montage, originally showed on Spanish TV, shows exactly how the Barcelona legend was guiding his team-mate into position on numerous occasions.
And when Dembele scored the second goal of the game, Messi looks absolutely ecstatic.
The duo embrace as the former leaves the pitch in the second half after being replaced by Aleix Vidal.
Dembele will certainly appreciate the help from a player regarded by many as the best to have ever graced the sport.
And in a recent interview, the 20-year-old admitted he is trying to improve his game.
“[I am] Losing the ball in silly ways,” he told Sport.
“I always try to fix it, every season.
“And here it’s not a joke.
“At Barca there are few balls given away and when you lose one, you see immediately and it’s not forgiven.
“The level of demand is very high.
“I have to fix this as soon as possible.”