The Argentina international and his Brazilian counterpart impressed earlier this campaign, but they have been unable to make much of an impact together recently - partially due to a string of fitness problems.
Los Blaugranas fell to a shock 1-0 defeat at Valladolid on Saturday with both forwards missing costly chances as they slipped four points behind Liga leaders Real Madrid, but Martino defended the pair and backed his side to move on.
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"You can’t guarantee they will always be synchronised just because it’s the best player in the world and the next best player in the world."
The Barca coach then turned to the second leg of the Champions League round-of-16 tie against Manchester City and warned his men not to take things lightly after their 2-0 away win in the first leg.
"Tomorrow I think Manchester City will make changes to the team. Sergio Aguero is very dangerous but they have many other players who are just as worrying.
"We have to think that 10 or 12 days ago, we played a very good match against Manchester City. I don’t see why we can’t do the same tomorrow and I am sure we will play well.
"We have to separate the league from the Champions League and we are at an advantage for tomorrow."