Slovakia's Dominik Hrbaty thrashed Russian sixth seed Dmitry Tursunov 6-1, 6-1 in the first round of the St Petersburg Open on Monday.
Tursunov, the only seeded player in action on the first day of the $1 million indoor tournament in Russia's second city, was clearly troubled by a painful shoulder, winning only 29 percent of his first serves.
"I injured my shoulder less than two weeks ago. I had to pull out of the Kremlin Cup, then lost in the first round at the Madrid Masters last week," the world number 26 told reporters.
"But I still have problems, especially when I serve. When you have pain it's hard to fight for victory."
Hrbaty, runner-up here in 2000, will now face unseeded German Rainer Schuettler, who had little trouble dispatching Kremlin Cup winner Igor Kunitsyn of Russia 6-2 6-3.
"I was simply not fit enough to play the match," said Kunitsyn, who won his maiden ATP title in Moscow eight days ago.
"After winning the Kremlin Cup I was sick for four days and just could not properly prepare for this tournament. I was too slow, was missing a lot of balls. Just a bad match altogether."
On the bad day for the home nation, Evgeny Korolev, a cousin of Anna Kournikova, was dumped out by Romanian Victor Hanescu 6-1 6-2.
Russia's second seed Nikolay Davydenko, who has clinched his place in the season-ending Masters Cup in Shanghai, takes on Australian Chris Guccione on Tuesday while top seed and last year's winner Briton Andy Murray begins his campaign against Serbia's Viktor Troicki on Wednesday.