Yamaha's Maverick Vinales set the pace in the Friday afternoon MotoGP practice session at Assen, followed by Italian trio Andrea Iannone, Danilo Petrucci and Valentino Rossi.
It took Marc Marquez five minutes to beat his own benchmark from FP1 with a 1m34.041s, which gave him a 1.2-second advantage over the field at the time.
But he didn't improve for the rest of his first run as he had several moments with his bike, including once running wide and on the gravel at the exit of Turn 7.
Andrea Dovizioso was the first rider to get close to Marquez with a 1m34.231s and the top two remained unchanged for the first half of the session.
Dovizioso was then next to improve again, the Italian narrowly outpacing Marquez with Suzuki's Alex Rins soon moving up into third, the top three separated by only 0.008s.
As qualifying runs on new soft rear tyres at the end of the session began, Vinales demoted Dovizioso with a 1m33.547s.
Vinales improved again to end FP2 with a 1m33.378s, with Suzuki's Iannone taking second, 0.121s off the pace. Petrucci was third, the Pramac Ducati rider narrowly beating Rossi.
Cal Crutchlow was the top Honda rider in fifth, as Marquez stayed on used hard rubber, and dropped down to eighth, also behind works Ducati duo Dovizioso and Jorge Lorenzo.
Rins was ninth ahead of Johann Zarco, who had a crash at Turn 9.
With everyone but Franco Morbidelli improving their FP1 times, it was the same 10 riders ending the day in the overall top 10 and currently set to make it to Q2.
Zarco beat Dani Pedrosa to 10th by 0.034s, followed by the Frenchman's teammate Hafizh Syahrin and top Aprilia rider Aleix Espargaro.
KTM duo Bradley Smith and Pol Espargaro were 18th and 19th respectively, the former having a bike problem and the latter crashing early in the session.