#5 Barcelona vs Manchester City, 2016-17 Champions League group stage

Pep Guardiola's return to his old club for the first time as Manchester City manager didn't go as planned. Messi, who had just returned from injury, scored his second hattrick against an English club as City were reduced to 10 men.
It wasn't a typical Messi performance but sometimes even a 50% Messi is good enough to decide games on his own as Barcelona beat Man City 4-0 at the Camp Nou.
#4 Barcelona vs Manchester United, 2010-11 Champions League final

Two years after beating United at Rome, Messi again inspired Barca to yet another Champions League title but this time at Wembley, where Barcelona tasted their first ever European glory.
The little maestro danced around the famous stadium and caused havoc. He scored his first ever goal on an English soil as Barcelona beat Manchester United 3-1 in the final.