Seeded players Marin Cilic and David Nalbandian were among Friday's quarterfinal winners at the $785,000 Aegon Championships, a grass-court Wimbledon tune-up.

The sixth-seeded Cilic, of Croatia, was leading Yen-Hsun Lu 6-4, 2-0 when the Taiwanese retired at The Queen's Club. Lu saw double-duty on Friday, as he opened his day with a 6-3, 2-6, 7-6 (7-5) upset of third-seeded Serb Janko Tipsarevic.

Cilic's semifinal opponent on Saturday will be former Queen's Club champion Sam Querrey, as the tall American got past Croat Ivan Dodig 7-5, 3-6, 6-3 on Day 5. Querrey titled here two years ago.

The tenth-seeded Nalbandian posted two wins on Friday, as the Argentine opened his day with a come-from-behind 4-6, 7-5, 6-3 third-round victory over France's Edouard Roger-Vasselin and capped it with another comeback victory, this time a 4-6, 7-6 (7-2), 6-4 quarterfinal decision against Belgian Xavier Malisse, who lost despite firing 18 aces.

Nalbandian played 4 hours, 13 minutes of tennis on Day 5.

The former Wimbledon runner-up Nalbandian will meet promising Bulgarian Grigor Dimitrov on Saturday. Dimitrov landed in the final four with a 4-6, 6-4, 6-3 upset of ninth-seeded South African Kevin Anderson, who fired 15 aces in a losing effort.

The 2012 Queen's Club champion will pocket $100,000.