Nikolay Davydenko lost his fourth straight match Tuesday, falling 3-6, 6-4, 6-3 to "lucky loser" Aljaz Bedene of Slovenia in the first round of the Power Horse Cup.
Bedene replaced Dmitry Tursunov of Russia in the main draw and needed less than 2 hours to add to Davydenko's opening-round losses in Munich, Madrid and Rome.
Viktor Troicki defeated Michael Russell of the United States 3-6, 6-3, 6-4. The Serb will play Grega Zemlja of Slovenia, who saved 13 of 15 breakpoints to beat David Goffin of Belgium 5-7, 6-0, 6-2.
Igor Sijsling of the Netherlands defeated Kazakh qualifier Evgeny Korolev 6-2, 6-4, serving 15 aces in his first clay court game of the season. He will play Germany's Philipp Kohlschreiber.