Nikolay Davydenko reached the Qatar Open quarterfinals by beating fourth-seeded Mikhail Youzhny 7-5, 6-3 on Wednesday.
The former third-ranked Davydenko has struggled in recent years with injury, but the Russian combined a consistent first serve with aggressive court play to eliminate the 25th-ranked Youzhny.
Davydenko broke Youzhny to take a 6-5 lead in the first set and won when Youzhny hit a forehand into the net. Davydenko kept the momentum going into the second set, forcing Youzhny to save a break point in the first and third games. At 2-2, Davydenko won three successive games to take control.
''Really today was (a) tough match,'' said Davydenko, who won the tournament in Doha three years ago. ''Maybe we didn't start well with so many mistakes. I know against Russians when you play in second round, it's not easy.''
Ahead of the season-opening tournament, the 44th-ranked Davydenko said he was targeting a place in the top 20 this year after failing to win a tournament in 2012.
''If I really concentrate and (practice) and play, I want to see results,'' Davydenko said.