Servia's fast lap of 221.343 mph was seventh overall in the six-hour practice session at the Indianapolis Motor Speedway, where most of the 22 drivers already qualified for the May 24 race shared track time with the drivers trying to find enough speed to make it into the 33-car field in time trials Saturday and Sunday.
The Spaniard, who finished 11th here last year as an Indy rookie, completed 73 laps in his first appearance on the 2.5-mile Indy oval this season.
Rahal Letterman did not take part in the first three IndyCar events this season due to lack of sponsorship and wasn't certain of racing here until last week. Servia lost his ride with KV Racing Technology at the end of last season due to lack of sponsorship and his ride with RLR wasn't made official until Wednesday.
"People keep asking me if I felt any pressure getting such a late start," Servia said. "But, the truth is this is the first day I've felt relief in five months."
Next among the non-qualified drivers was Townsend Bell, who got his ride with KV late last week. He posted a lap of 220.938 as he worked to get enough speed to join two teammates already in the lineup - Mario Moraes, who led Thursday's speed chart at 222.739, and Paul Tracy.
Other fast drivers Thursday among the non-qualified entries included E.J. Viso at 220.085, Alex Tagliani at 218.986, Ryan Hunter-Reay at 218.894 and John Andretti at 218.721.
The 2.5-mile track was closed after the second round of qualifying ended last Sunday and didn't reopen until Thursday. That led to a busy day, with the already qualified drivers working on race-day setups and the non-qualified drivers working their way up to speed.
Among the other drivers on the track and yet to qualify were 1996 Indy winner Buddy Lazier, making his first appearance of the month, Milka Duno, hoping to join already-qualified Danica Patrick and Sarah Fisher in the lineup, and Indianapolis rookies Robert Doornbos, Nelson Philippe and Stanton Barrett.
Doornbos was back on track for the first time since hitting the wall in practice on Saturday, his second crash in as many days. Andretti, Tagliani and Philippe were also returning from crashes last week.
Mike Conway, another rookie, spent Saturday night in an Indianapolis hospital with bruised lungs and a slight concussion after a hard crash earlier that day. He was to be examined by track doctors Friday morning to determine if he could get back in a race car in time to attempt qualifying.
"I'm feeling OK now," said Conway, a 25-year-old Englishman. "I was sore on Tuesday, but I feel ready to get back into the car."
Davey Hamilton, the slowest among the drivers already qualified at 221.956, also got on track late in Thursday's practice.
Ryan Briscoe, who will start in the middle of the front row, between pole-winning teammate Helio Castroneves and 2007 race winner Dario Franchitti, was second on the speed chart at 222.406. He was followed by two-time Indy winner Castroneves at 222.395, 2008 race winner Scott Dixon at 222.374, Tony Kanaan at 221.890 and Franchitti at 221.516.
Friday will be another full day of practice, with the final 11 positions scheduled to be filled on Saturday. Any remaining drivers can attempt to bump out the slowest qualifiers in the field on Sunday, the fourth and final day of time trials.