STOCKHOLM: Tommy Haas and Feliciano Lopez put aside last week's injury dramas in Asia as the pair of seeds returned to apparent robust health with wins into the second round of the Stockholm Open Wednesday.

Number two Haas and the eighth-ranked Lopez both secured straight-set success at the Kungligahallen with neither man requiring more than an hour on court.

Haas, who withdrew after one losing set against Rainer Schuettler last week in the Shanghai second round, showed perfect fitness as he crushed 17 aces in 55 minutes in his 6-3, 6-4 defeat of Frenchman Florent Serra.

Lopez, seeded eighth, moved through nicely four days after pulling up lame in the Shanghai semis to hand Rafael Nadal a 6-1, 3-0 result, and was light on his feet in a defeat of Latvian Ernests Gulbis 6-2, 6-4.

Germany's Haas now stands 2-0 over Serra, the world number 68, with the Florida-based seed a two-time Stockholm semi-finalist from 2004 and 2007.

Haas said that his earlier shoulder problem now appears to be under control after his precautionary withdrawal in Shanghai.

"It's okay, it's holding up. There were a lot of nice quick points today which suited me well. I served extremely well and I'm happy with how I played, but there's still room for improvement of course."

Serra dropped to 21-27 on the season after last winning an ATP-level match in the Us open first round. Halle, Germany, champion Haas won his 31st match of 2009 against 16 defeats.

Haas will next face Jarkko Nieminen, back in action after a wrist injury which kept the Finn away for nearly four months followed by a recent virus form which he only recovered in time to play a Danish Challenger last week.

Top seed Robin Soderling was opening his home campaign against lucky loser Giovanni Lapentti of Ecuador later while number three Spanish veteran Juan Carlos Ferrero was playing former Australian Open finalist Marcos Baghdatis.