The former France international believes that the Argentine spent the entire Champions League quarter-final second leg "walking around the pitch"
The Argentine covered just 6.8 kilometres of ground in his side's 1-0 loss at the Vicente Calderon, half of match-winner Koke and only 1.4km more than Barca keeper Jose Pinto, and spurned two clear-cut chances in the first half.
The former France international believes that the 26-year-old's performance was a sign of disrespect to the crowd and that he did not show enough urgency.
"[On Wednesday] Messi took people for idiots! He spent his time walking," he told beIN Sport.
Sagnol also took the time to praise Atleti coach Diego Simeone, saying he was a difficult opponent to face during his playing days.
"I had the chance to play against Simeone," he added.
"He was a real dog on the pitch."