Updated

Former champion Tommy Haas was an easy second-round winner Thursday at the Delray Beach International Tennis Championships.

The oft-injured one-time world No. 2 and second-seeded Haas handled Uzbekistan's Denis Istomin 6-4, 6-1 at Delray Beach Tennis Center.

Haas, who was the titlist here back in 2006, will meet capable Croat Ivan Dodig in the quarterfinals.

Talented Latvian Ernests Gulbis, a qualifier this week, ousted third-seeded American Sam Querrey, 6-4, 4-6, 7-6 (7-4), in 2 hours, 14 minutes. Gulbis was the Delray Beach champion in 2010.

Meanwhile, five-time Delray Beach finalist Xavier Malisse was sent packing on Day 4, as Spanish qualifier Daniel Munoz-De La Nava doused the eighth-seeded Belgian 7-6 (7-3), 3-6, 6-3.

Malisse was the champion here in 2005 and 2007 and runner-up in 1999, 2001 and 2006.

In other second-round action, Dodig topped Russian Evgeny Donskoy 6-3, 7-5, France's Edouard Roger-Vasselin erased 6-foot-10 Croat Ivo Karlovic 6-4, 7-5 and Lithuanian lucky loser Ricardas Berankis overcame American wild card Jack Sock 3-6, 6-4, 6-1. Karlovic was the Delray Beach runner-up to Gulbis three years ago.