Graham Hunter says Atletico Madrid must arrive at the Camp Nou on Saturday mentally prepared to win the La Liga title on Barcelona soil.
The table toppers passed up a golden opportunity to clinch the crown on their own patch last weekend when they were held by a resilient Malaga side and the reaction at the final whistle, when it became apparent Barcelona had only managed a draw against Elche - and a late winner for Atletico would have won the title - was one of disappointment from the home fans.
However, Hunter says Atletico still have a great opportunity to win their first championship since 1996.
And he thinks boss Diego Simeone must 'buck up' the players so they perform to their maximum in their final league game of the campaign, where even a draw would secure the title.
"The body language was worrying," said Hunter.
"Over a career analysing football rather than playing it, you feed off the winners who tell you how they've won.
"It's a delicate process psychologically, getting over the line, but the majority of these Atletico players haven't done it before.
"Players, fans and Simeone all had their shoulders down, with looks of bewilderment. It was as if it had to be won in front of their own fans, as if this was the opportunity lost - when we all know it's not.
"Two of the three results at the Camp Nou favour them - but Simeone has a job to do re-adjusting the impression he gave his players because he looked almost as defeated as they did at the final whistle. He has to buck them up.
"I thought [his reaction] was a miss-step. Almost as much of a miss-step as missing those chances in the second half."
However, Hunter says Atletico - who have not been defeated by Barcelona in their last five meetings in all competitions, including this season's Champions League semi-finals - have found a formula to stifle the Catalans and it is all on Tata Martino's team to find a way through this weekend.
"In the 11 games before Simeone took over Barca scored 38 times against Atletico," explained Hunter. "In Simeone's first two games they scored six times and Lionel Messi just loved it. It was like shooting fish in a barrel.
"But since December 2012 Messi hasn't scored. It's about six games now since he scored against them. He's not even creating chances. They are marking him, fouling him and working harder. They've snuffed him out.
"Martino has to shake off the intensity this week and say: 'How do I open this game up so the best player in the world, Messi, can win us the title?'"
Guillem Balague also reckons Barcelona have problems of their own.
After questioning their preparation for their match with Elche, he suggested they need to produce something special to unlock a defence they have found so difficult to break through in recent contests.
"Barcelona haven't been able to pass the ball quickly enough," he said. "They've not had enough movement off the ball and they've not had enough tactical work on the attack.
"There's been too much dependence on Messi getting the ball at the right time when he's been surrounded by players, against a team that defends really well.
"It's a battle of a team committed with a clear idea of what they have to do against a team full of doubts with extraordinary players."