Argentina boss Jorge Sampaoli suggested his squad limits the impact of Lionel Messi at the World Cup, while Portugal manages to get the best out of Cristiano Ronaldo.
Messi, who missed a penalty in Argentina's draw against Iceland in its opening Group D match, was frustrated for much of Thursday's clash with Croatia, as a 3-0 defeat put Sampaoli's side on the brink of an early exit.
Sampaoli has an array of attacking talent at his disposal, but has struggled to make it click, with Messi often tasked with directing all of Argentina's play.
While Messi is yet to get off the mark in Russia, rival Ronaldo has netted four times in two games, with his blistering header securing victory for Portugal against Morocco on Wednesday.
But the former Sevilla boss insists Messi should not be compared to Ronaldo, given the differences between Argentina and the current European champions.
"Ronaldo is an excellent player, you can look at all he has achieved in his career," Sampaoli said.
"Right now, we shouldn't compare these two players. With the reality of the Argentina squad, it sort of clouds Leo's brilliance.
"He's limited because the team doesn't gel with him ideally, as it should. As coaches, we need to deal with this.
"I've always looked for the best position for my players on the pitch. The playmaker carries a special burden. We didn't manage to find link-ups that would benefit Argentina and Leo."
Sampaoli has plenty of talent to choose from, but has struggled to fit the likes of Gonzalo Higuain, Sergio Aguero and Messi into the same side, while Juventus star Paulo Dybala has been ineffective from the bench.
Argentina must beat Nigeria in its final group game to stand a chance of progressing, and is relying on Iceland slipping up, but Sampaoli still has faith that his squad's quality can shine through.
"I thought we would put a lot of pressure on Croatia, in their half of the pitch, but after they scored we kind of lost our way," he added.
"We were emotionally broken and we didn't have any footballing way to change the course of events. If you don't have momentum, it's very difficult to move forward.
"I value my players a great deal, I think this is an excellent squad, but at no stage did we really gel and come together. We need to take advantage of this last match, fight for it, and hopefully go through."