Charge to the front sees Jack in P1 for two laps before just missing podium.
Jack has secured his third top-four result in the opening five races of 2019 at Le Mans, leading the French Grand Prix for two laps on the way to a fourth-place finish on Sunday afternoon.
Starting from third place after a superb effort in a semi-wet Q2 on Saturday, Jack made a solid getaway and retained that spot after the first lap, and pushed his way past Danilo Petrucci (Ducati) to set off after race-leader Marc Marquez (Honda) on the third lap of the 27-lap race. On lap five, Jack took Marquez for the lead at the Turn 2 chicane, and held that position for two laps until the reigning world champion successfully retaliated at the same corner.
With Marquez opening up a race-winning gap, Jack was relatively comfortable in second place for the next seven laps, before Petrucci and fellow factory Ducati rider Andrea Dovizioso started to reel him in as he battled with fading tyres. Dovizioso passed Jack on lap 17, with Petrucci demoting the Australian from the podium places eight laps from home.
Jack made a valiant final charge for the rostrum inside the last two laps, but had to settle for a second fourth-place finish in France in as many years, and his second fourth place this season after he also scored 13 points in Argentina in round two.
Petrucci was 0.8secs ahead of Jack at the finish, with Jack managing to hold off a fast-finishing Valentino Rossi (Yamaha) by a tenth of a second at the chequered flag.
“I had a great time,” Jack said.
“The feeling with the bike was very good. Maybe I pushed too hard to try to stay ahead of Marquez. It was more catching Marc where I hurt the rest of my race, the laps I did narrowing the gap to him.
“I learned a lot running with those front guys, and actually being one of those front guys.”
With 42 points, Jack jumps one place in the championship standings to sixth overall ahead of the next race, the Italian Grand Prix at Mugello on Sunday June 2
Full race results from France can be found on motogp.com here.
Photos courtesy of Pramac Racing.