The Hoops meet the Catalan giants at the Nou Camp in the Champions League tomorrow night and the Israeli international is well aware that there are a number of other world-class performers in Tito Vilanova's squad despite joking about man-marking the Argentine ace.
"I think 11 players will mark him! But seriously, we're not just playing Messi," said Kayal.
"We believe we can do something in this group, now's the chance to prove it."
And Kayal added that confidence in the Celtic camp is high following their 5-0 league win at St Mirren on Saturday.
"We can do something in the Nou Camp," Kayal said.
"Barcelona are the best team in the world, but we are full of confidence and we go there with belief.
"They have the likes of Xavi, Iniesta and Messi but it's a chance for Celtic to prove we are also at that level.
"It's not easy to win 5-0 in the SPL but we made it easy for us and did our jobs well.