Scott Dixon will start Saturday's Bommarito Automotive Group 500 race at the Gateway Motorsports Park from pole position after qualifying was cancelled and determined by championship standings.
Dixon therefore starts ahead of Alexander Rossi, who was quickest in practice, with Josef Newgarden lining up third.
Poor weather and heavy rain forced the cancellation of the session to allow more time for an extended final practice in the evening, if conditions improve. That session is due to last 90 minutes
As per the rules, the starting grid for the 248-lap race will be set on points.
"I think, ultimately, everybody wants to qualify," Dixon said. "It's just difficult when you're coming into a track with a new aero kit and we only had, I think, 22 minutes of green time.
"In many ways, I think INDYCAR made the right decision as far as trying to put a priority on getting some running tonight in hopefully dry conditions that will benefit everybody for race setup and that kind of stuff later on. It was going to be hard, I think, schedule-wise to try to get everything in."
Dixon does not earn a bonus point or credit for the pole position, though he felt he could have been in contention for it given his pace.
"I think our car was pretty good,” he added. "Would we have got the pole? Maybe, maybe not, but right now we're just trying to focus on getting some changes for tonight's practice and obviously make the race car a little bit better."
Rossi was fastest in the opening practice that saw just 22 minutes of green-flag time, with a lap of 184.424 mph in the #27 NAPA AUTO PARTS Honda.
"We have a little bit of an advantage because we tested here about three or four weeks ago. All of the Andretti Autosport cars had a pretty good baseline to start from, so it’s great that the NAPA Honda was up front.
"But with these changing conditions and the unknowns of different rubber going down, we really don’t know how it will translate. Hopefully we can carry that forward."
Sebastien Bourdais was third quickest in practice with a lap of 182.675 mph in the #18 Team SealMaster Honda, but starts down in ninth behind James Hinchcliffe.
For a full qualifying list, click here.
