Please Wait . . .
The Blaugrana found that out to their cost in a Clasico clash with arch-rivals Real Madrid on Sunday.
Quique Setien's side headed to Santiago Bernabeu perched at the top of the Liga standings, but drew a blank in a 2-0 defeat and have now slipped back down to second.
Messi was unable to conjure up another talismanic performance in his latest outing against old adversaries, and the supporting cast offered him little assistance.
"He is Barca's match winner and if he is well defended their chances of being threatening in attack are severely reduced.
"At the moment, he is the only Barcelona player taking responsibility with the ball, shooting from outside the box and trying to unbalance opposing defenders.
"No one else in the team seems capable of helping him in that department. That makes things tough for the Argentinian.
"Without Luis Suarez, Barcelona loses a lot because, apart from Messi, they have no other player who can surprise opponents. The Uruguayan works hard, is fearless and puts opposing defences to the sword very often.
"Barca are missing Suarez and, in his absence, they're putting all the responsibility on Messi.
"When they lose, everyone starts asking what happened to Messi. He is always the target of fans' frustration when things don't go so well for the team but that's unfair."
Rivaldo believes Barca blew a "big chance" to take control of the 2019-20 title race in the Spanish capital, with an intriguing battle for domestic supremacy seemingly set to be determined by the finest of margins.
The Brazilian added: "Quique Setien's players knew El Clasico was a big chance for them to run away at the top of La Liga. By losing at Santiago Bernabeu, they should feel they wasted an opportunity at an important stage of the season.
"Barca played well in the first half and could have scored the first goal, which would have changed the approach of both teams. But they weren't clinical and in the second half Madrid managed to play better and take advantage of their chances.
"In these kinds of matches, every detail can make the difference and if Barcelona had scored first I'm sure things would have been different.
"But it didn't happen that way this time and Madrid ended up taking more risks in the second-half and were rewarded for that."
Barcelona will be back in action on Saturday when they play host to Real Sociedad.