Tommy Haas was down 3-6, 2-3 before pulling out of his semifinal match against Paolo Lorenzi.
Matthew Stockman/Getty Images

SAO PAULO -- Top-seeded Tommy Haas retired with a shoulder injury while losing 6-3, 3-2 to Paolo Lorenzi of Italy in the Brazil Open semifinals on Saturday.

Haas said he "felt a lot of pain" in his right shoulder when he slammed his racket to the ground in frustration after losing his serve at 3-3 in the first set. He kept playing despite needing medical treatment several times, and finally gave up after going down another break in the second set.

The 12th-ranked German said the pain was "getting worse during the match" and didn't allow him to "compete the way" he wanted.

The 32-year-old Lorenzi, ranked 114th, will play in his first ATP final against either Thomas Bellucci of Brazil or Federico Delbonis of Argentina. Lorenzi had previously never advanced past the quarterfinals.

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