Sturm, 35, is currently finishing off preparations for his own title defence against old rival Sam Soliman on May 31 and sees Martinez keeping a tight hold of the WBC belt in the Argentines possession one week later.
“It’s an intriguing fight,” Sturm told World Boxing News.
“Both are great, great fighters, but I think Martinez is too big, too strong, and in certain ways too fast for Cotto and I see him winning inside the distance.
“That is the way I see it, but only if he is injury free. If not, Cotto will make it a hell of a night for him.”
German-native Sturm has not fought outside his home country since an ill-fated and controversial points defeat to Oscar De La Hoya in 2004, but the three-time world title holder would be interested in facing whoever eventually comes out on top next month.
“I’d be open to fight either one of those guys as a unification is always great,” said Sturm.
“Both are very talented fighters, but I believe I could beat either one of them to be honest – if a fight could ever be made.”
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