Haas, from Germany, defeated Devin Britton 6-4, 7-6 (7-3) in a brisk 73 minutes despite Britton's 15-ace attack. There was just one service break in the match, with that giving Haas the first set.
Sixth-seeded German Philipp Kohlschreiber needed to rally for a 6-7 (7-9), 6-1, 6-3 victory over Rajeev Ram and No. 7-seeded American Sam Querrey took out Teimuraz Gabashvili 6-3, 6-2 in 55 minutes but eighth-seeded Jeremy Chardy fell 6-3, 6-1 to Germany's Bjorn Phau.
In first-round matches Tuesday that didn't involve seeded players, American Michael Russell topped Kim Tae-im 7-6 (8-6), 6-1; Lithuanian Ricardas Berankis defeated Robby Ginepri 6-7 (5-7), 6-2, 6-3; and German Benjamin Becker had four service breaks in a 6-4, 6-2 win over Tim Smyczek.
Kim was inserted into the SAP Open field when third-seeded Mardy Fish withdrew due to a knee injury.
The tournament schedule calls for the finals to be played Sunday with the champion taking home $90,925.
Wisconsin business offering 'therapeutic cuddling' forced to close
Selena Gomez drops F-bomb, walks off stage during Jingle Ball performance