Pavement never seemed like a band that sweated the details. With their wry, stream-of-consciousness lyrics and disjointed structures, their songs played like first drafts of songs the group never got around to cleaning up, and the band projected a devil-may-care attitude that typecast them as slackers. That lackadaisical confidence defined the group’s image, but it also fueled the misperception that they were genuinely apathetic about their music and their career. On the contrary, says percussionist Bob Nastanovich. One of the things he remembers most vividly about Pavement in the ’90s was the constant pressure the group put on themselves.

“We just felt like expectations were really high,” Nastanovich says. “There’s that pressure you have on yourself, because you care about your band a lot, and you want your band to be the best it can be. We really wanted to back up a lot of the nice things that were said about us by critics, but there was a lack of preparedness on our part that was due a lot to the fact that because of where we all lived, we didn’t have any normal rehearsal schedule. And, of course, whenever a band is trying to sell a record, you don’t want to let down your record label. We didn’t want to disappoint anybody.”

Playing Pavement’s reunion tour a decade after the group broke up, Nastanovich no longer feels the weight of expectations.

“There’s just this vibe around the whole reunion where there’s not as much pressure,” he says, “maybe because it’s a celebration of what was.”

Make no mistake about it: Pavement’s reunion tour is about the past, not the future, and it comes with an expiration date. Where the reunited Pixies continue to tease fans with ever more tour dates and even vague talk of a new album, Pavement announced their return with an explicit warning to those who might read too much into it: "Please be advised this tour is not a prelude to additional jaunts and/or a permanent reunion."

After having toured on and off since March, Pavement will play a spate of shows this month, which they’ll chase with a handful in October and a couple South American dates in November, then they’ll go their separate ways, as frontman Stephen Malkmus completes a new record with his band The Jicks, drummer Steve West finishes a new album with his band Marble Valley, guitarist Scott Kannberg cuts another record of his own, bassist Mark Ibold likely returns to Sonic Youth, and Nastanovich picks up where he left off in the horse-racing industry, where he does statistical analysis. So long as Pavement’s booking agent does his job, there will always be the possibility of additional shows, but given Malkmus’ reticence about the reunion, nobody’s banking on it.

Malkmus was the last member on board for the reunion, and in the handful of interviews he conducted about the tour, he was unable to muster even cursory enthusiasm about it—unsurprising, given how little nostalgia he’s shown for the band since it broke up. It was Kannberg, not Malkmus, who tasked himself with keeping the band’s legacy, curating Matador Records’ exhaustive reissues of the group’s albums.

On stage with Pavement again after all these years, Malkmus can sometimes appear disinterested—no real change from the band’s initial run together—leaving Nastanovich to fall back into his old role. He joined Pavement as a second drum player, covering for the group’s unreliable original drummer, Gary West, but after West’s departure Nastanovich took on a more iconic role, supplementing not just the drummer, but also the frontman. In concert he works the crowd with shouted backup vocals and takes the lead on rowdier songs, delivering the energy that Malkmus can’t muster.

“Entertaining the crowds is a pretty easy, fun part of the job,” Nastanovich says. “The fans we have are very receptive, and they just want to have a good time. The pressure for me is that I was not a musician before Pavement and I really haven’t been since, and my skills are pretty rudimentary. I remember playing with bands like Stereolab and the Dirty Three and The High Llamas, and getting to know these people who were so advanced musically that whatever they were doing in the context of their own bands was easy to them, almost boring. For me, though, I was always terrified that I might screw something up even though our songs aren’t that difficult.”

Though Nastanovich’s enthused, sometimes imprecise contributions can lend to the ramshackle aesthetic that Pavement fans generally celebrate, he says the goal is never to be deliberately sloppy. Despite their reputation, Pavement cares about how they sound.

“Occasionally I’ll draw the ire of my band mates when I’m overstepping my boundaries, because I’ll try to over-embellish songs, and I think I overindulge, and that can be to the detriment of the songs,” Nastanovich says. “Some of our songs are pretty, and you don’t want to make them sound ugly.”

Pavement plays the Pabst Theater on Tuesday, Sept. 14, at 8 p.m. with openers No Age.