Johann Zarco grabbed a shock MotoGP pole position at a wet Motegi, as slick-tyre gambles backfired for Marc Marquez and Valentino Rossi and Maverick Vinales was eliminated in Q1.
After setting the quickest time of the weekend so far in FP4, Marquez seemed nailed on for pole when he immediately bettered his own benchmark with a 1m53.903s, going 1.8 seconds clear of the pack.
But the Honda rider made a tactical error when he opted for slicks on his second run, and the track had not dried out enough for dry-weather tyres, despite the rain abating.
Valentino Rossi proved slicks were not the tyres to be on when he lapped 19 seconds off the pace early on, and an earlier crash in FP4 meant the Italian could not quickly switch back to wets.
With Marquez unable to improve on slicks, Tech 3 Yamaha's Zarco stole the top spot away with a minute left to run with a time of 1m53.469s, a full four tenths faster than the Spaniard, to earn his second MotoGP pole.
Pramac Ducati rider Danilo Petrucci rubbed salt in Marquez's wounds by going second-fastest shortly afterwards with a time 0.318s adrift of Zarco.
Marquez held on to third ahead of Aprilia's Aleix Espargaro, lead factory Ducati rider Jorge Lorenzo and the second works Honda of Dani Pedrosa.
KTM impressed in the wet conditions by getting both of its bikes out of Q1, with Bradley Smith taking his best grid slot of the year in seventh ahead of team-mate Pol Espargaro.
Andrea Dovizioso could no more than ninth on the second of the factory Ducatis, ahead of Suzuki pair Alex Rins and Andrea Iannone, the former taking a career-best grid slot.
With only a couple of minutes of track time on wets, Rossi was 12th and slowest in Q2, 4.317s off the pace.
The first qualifying segment was topped by Pol Espargaro, who made an early move to the top of the times with a 1m55.793s before later improving to a 1m55.258s.
That put him six tenths up on Smith, who made it out of Q1 for only the second time this season, edging out Loris Baz's Avintia Ducati by just 0.016s.
The big story was title contender Vinales missing out on a spot in Q2 with a final effort 0.072s slower than that of Smith, which leaves him down in 14th on the grid behind Baz.
Also missing out on a berth in the pole shootout was LCR Honda rider Cal Crutchlow, who was on course to make it through on his final lap before a big wobble left him fifth-fastest. The Briton starts 15th.
After a major highside crash in FP4, Tech 3 stand-in Kohta Nozane was slowest of all in Q1, and is set to line up 24th and last for his MotoGP debut - one place behind Yamaha testing mentor Katsuyuki Nakasuga.
|1||Johann Zarco||Tech3 Yamaha||1m53.469s|
|2||Danilo Petrucci||Pramac Ducati||0.318s|
|13||Loris Baz||Avintia Ducati||2.393s|
|15||Cal Crutchlow||LCR Honda||2.483s|
|16||Alvaro Bautista||Aspar Ducati||2.823s|
|17||Hector Barbera||Avintia Ducati||3.199s|
|19||Tito Rabat||MVDS Honda||3.434s|
|20||Karel Abraham||Aspar Ducati||3.675s|
|21||Hiroshi Aoyama||MVDS Honda||3.688s|
|22||Scott Redding||Pramac Ducati||4.318s|
|24||Kohta Nozane||Tech3 Yamaha||8.261s|