Grosjean set the 10th-fastest time in Q1 with a lap of 1:34.892 around the 5.513-kilometer (3.426-mile), 20-turn track. Magnussen was 12th quickest with a lap of 1:34.972. Each driver handily made the top-15 cutoff to advance to Q2.
In Q2, Grosjean earned the seventh-fastest time with a lap of 1:34.419 while Magnussen was 12th with a lap of 1:34.732. Only the top-10 drivers move on to Q3.
Into Q3 for the 11th straight time - a streak that began June 23 in qualifying for the French Grand Prix and is the longest such stretch of his Formula One career - Grosjean qualified a solid eighth with a lap of 1:34.250.
Both Grosjean and Magnussen ran exclusively on the Pirelli P Zero Purple ultrasoft tire throughout qualifying.
Before Grosjean, Magnussen and the rest of their Formula One counterparts participated in knockout qualifying, they had one final practice (FP3) to dial in their racecars for a quick lap around the track. Grosjean started on the Red supersoft tire and ran 14 laps before switching to Purple ultrasofts. Magnussen did the opposite. He began FP3 on ultrasofts and turned eight laps until changing to supersofts. After five laps, Magnussen returned to ultrasofts to finish out the session.
Grosjean totaled 19 laps and set the 10th-fastest time with a 1:35.468 on his 17th tour. Magnussen also tallied 19 laps and earned his best time on his 16th lap - a 1:35.770 that put him 13th overall.
Romain Grosjean: "I was happy to be in Q3 again. It's too bad Kevin couldn't quite make it into the session. Maybe we're not quite best of the rest this weekend, at least with the conditions we had today. Hopefully, we'll have a bit more for the race tomorrow. I'm really looking forward to the race. We've got one car that can choose its tires for the race start, and then I'll start on the ultrasofts. It should be about 15 degrees hotter in terms of track temperature. There's a lot of difference for tomorrow. I think we're pretty much in a good spot. I think we've got a good car. It's exciting to know that we're in the mix there with Force India sixth and Renault seventh. This midfield battle is pretty amazing."
Kevin Magnussen: "I was struggling a lot in sector three, the low-speed corners. I just had a bit too much instability at the rear, which I struggle a little bit with. My lap was okay. P12 is not satisfying, but we can do some stuff tomorrow with strategy and, hopefully, we'll get into the points. The midfield is so close. It's only something like two tenths of a second from where I am to the top of that fight. I just missed that tenth or two to get me in front there. We missed that today, but who knows tomorrow. With strategy a bit more open for people outside of the top-10, maybe there'll be an advantage there. We'll see what we can do tomorrow."
Guenther Steiner: "This morning we had the first proper running of the weekend. We learned quite a bit in FP3. Then qualifying eighth and 12th, that's our best qualifying result here in America, so at least we're going uphill. We were never that good here previously. I think we're in a good position to score points tomorrow with both cars. Romain had a little bit of oversteer, unfortunately, in the last corner, so he was eighth instead of sixth, but that's racing, and some you win and some you lose. We're still in a good position. Let's go racing tomorrow."