Messi has scored the crucial goals against Bosnia-Herzegovina and Iran to give Argentina back-to-back wins in Brazil, but Alejandro Sabella's side has only netted one other - an own goal in its opener last weekend - and the rest of the forward department has come under fire for the disappointing displays.
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"El Pipa [Gonzalo Higuain] has been a little bit injured and didn't play the two games before the competition, while Kun [Sergio Aguero] has also had some injury problems," Di Maria told reporters at Argentina's training base outside Belo Horizonte on Sunday. "It's difficult when you have injuries, it affects you, and it affects how you adapt alongside your teammates."
"But we will all look to improve," he added. "It was important to get the six points (from the Bosnia and Iran games) to qualify for the next round. Now we will try to help Messi so that things are a little easier."
Asked what Messi can do that he can't, Di Maria joked: "Everything — Leo is Leo and he always appears in the moments when nobody else does. He scored a great goal [against Iran]. When he hits it, there is little they can do. We're happy to have him. Lots of people were criticizing him and saying he wasn't playing well, but he has shown that's not the case."