Marc Marquez gave his Moto2 championship hopes a major boost after winning a rain-affected TT Assen that saw series leader Stefan Bradl crash out. Rain that had fallen at the end of the 125cc race continued to fall but Marquez, Bradley Smith, Kenan Sofuoglu and Yuki Takahashi coped brilliantly to leave the rest of the field behind.
That included the likes of Stefan Bradl who quickly fell back from pole position. Marquez immediately demoted him at turn one and by the end of the first lap he had dropped to fifth. Simone Corsi seemed to have more grip than anyone else in the early stages and led from Smith, Marquez, Sofuoglu and Mike Di Meglio who was flying on the second Tech 3 machine.
Lap three was a bittersweet one for the French team as Smith grabbed the lead at the Strubben hairpin, but Di Meglio's promising run ended a few corners later with an accident, shortly after taking fourth from Sofuoglu.
Corsi began to plummet down the order just as quick as Bradl had been. By lap six, the Italian had dropped behind the wet-weather specialist Anthony West into sixth while Bradl was all the way down in 13th.
The top four were in a class of their own though and were the best part of ten seconds clear of West in fifth as the race approached half distance, allowing them to fight it out between them. Sofuoglu put the hammer down on lap ten, overtaking Marquez at the final chicane before diving past Smith to take the lead halfway around the next lap.
If the Turkish rider's plan was to storm off into the distance, he was in for a surprise as Smith and Marquez remained hot on his heels, with Takahashi keeping a watching brief. On lap 14, Marquez breezed past Smith into second and began to pressure Sofuoglu.
With the wet tyres becoming increasingly worn a track that was starting to dry out, Sofuoglu was struggling to hold the charging Spaniard at bay and inevitably lost the lead on lap 17 with Smith also sneaking through.
All hell broke loose on the next lap though as Smith got his nose back in front, with Sofuoglu running wide in an attempt to take the lead for himself. Marquez seized the opportunity to repass the Briton at the chicane with Takahashi seizing the opportunity to take third from Sofuoglu.
The Japanese rider had kept himself out of trouble but just as he was putting himself in a winning position, the Gresini rider crashed out at De Bult. The conditions were catching out the very best though as championship leader Bradl slid off with three laps to go. The German had recovered back up to ninth but lost control as he tried to keep Esteve Rabat behind him, resulting in his first DNF of the season.
Following the accident for Takahashi, Marquez had the benefit of a comfortable lead and cruised home to win by 2.3s. Sofuoglu got the better of Smith with four laps to go to claim his first Grand Prix podium but the British rider still finished an impressive third.
Equally impressive were the performances of West who took fourth from 20th on the grid, and Alex de Angelis who came from 22nd to fifth. Mattia Pasini, who showed good pace in the wet at Silverstone before crashing, stayed upright this time to take sixth ahead of Esteve Rabat, Thomas Luthi and Randy Krummenacher.
Max Neukirchner also rode an inspired race to finish tenth after starting at the back of the grid. Kev Coghlan couldn't score points this time, finishing 21st, while Scott Redding had a miserable afternoon and trailed home a lap down in 24th.