Now ranked No. 169, Haas received a wild-card entry into the $125,000 Dallas Tennis Classic and Wednesday faces Italy's Andreas Seppi, who is seeded third and ranked 46th in the world.
Croatia's Marin Cilic, ranked No. 24, is the tournament's top seed and follows Haas onto the main court at the Four Seasons on Wednesday in a first-round match against Italy's Simone Bolelli (No. 110).
In first-round play Tuesday, former Baylor standout Benjamin Becker -- who won the NCAA singles title for the Bears in 2003-04 -- capitalized on his wild-card entry to post a 7-6 (7-1), 6-3 victory over Russia's Igor Kunitsyn. In another first-round match, Houston-based Michael Russell completed a 6-0, 6-0 whitewash of Brookhaven Country Club teaching pro John Nallon, who received one of four wild cards into the singles draw along with Germans Haas and Becker and Amir Delic of Bosnia-Herzegovina.
In the tournament's first upset, Italy's Flavio Cipolla scored a 6-4, 6-1 victory over No. 2 seed Alex Bogomolov of Russia. No. 5 seed Yen-Hsun Lu of Chinese Tapei posted a 6-3, 6-4 triumph over Delic in another first-round match.
The Dallas Tennis Classic is a Challenger level event on the ATP Tour with a 32-player singles draw and a 16-team doubles draw. But because the tournament falls between Masters Series events in Indian Wells, Calif., and Miami, players ranked in the top 50 are eligible to enter without obtaining a wild card. The DTC field features eight players ranked in the top 70 of the latest ATP Tour rankings.
This is the second Challenger event in Dallas in the space of five weeks. In February, Florida-based lefty Jesse Levine won the $100,000 yp Challenger of Dallas at T Bar M Racquet with a straight-sets victory in the final over Belgium's Steve Darcis.