Piastri had taken one of the most impressive pole positions of the year on Friday, by nearly 0.5secs, but in the end McLaren paid the price for running slightly more downforce than Verstappen.
Piastri was always going to be vulnerable on the first lap – it is notoriously difficult for a pole winner to hold the lead on the first lap at Spa because of the long run from the La Source hairpin through the fast Eau Rouge swerves to the Les Combes chicane.
Sure enough, Verstappen tracked Piastri from the start and passed the McLaren around the outside into Les Combes.
Once in second place, Piastri could stick with Verstappen but was never able to be close enough at the end of the straight to strike back.
The closest he got was on lap 11, but the Red Bull’s straight-line speed was enough to allow Verstappen, even without the DRS overtaking aid, to stay just out of reach.
Although Norris closed quickly on the lead pair, he too was unable to make progress.
Verstappen said: “It worked out really well. That is the only real opportunity you are going to get against them, and we got it.
“Then I knew it was going to be tough to keep them behind, and then it’s cat and mouse, playing with DRS and battery usage. The whole race was within 0.7secs. It’s a great result for us.”
Piastri said: “I tried my best to not give too much of a tow (on the first lap), but I didn’t have enough straight-line speed and I didn’t have enough for the next 15 laps either. Pretty happy with it but a bit frustrated I couldn’t get past.”
The race raises a difficult quandary for McLaren in terms of how to approach the grand prix.
The temptation will be to take off a little downforce to allow them to be more competitive on the straights, so that if they end up behind Verstappen again they have the possibility to pass.
But with rain threatening on Sunday, that could make the car too difficult to drive in the wet – as Verstappen found in the British Grand Prix, when he slumped to fifth in a wet race after taking pole with a low-downforce set-up.
Piastri said: “It’s a great question. The weather is looking pretty bad for tomorrow so you don’t want to take off too much wing, but I don’t want a repeat of today.”
Behind the top three, the race was as static as at the front.
Leclerc, once he dropped behind Norris, was comfortable in fourth place. And there were no place changes in the rest of the top-eight points positions as Haas driver Esteban Ocon took fifth, from Williams’ Carlos Sainz, Haas’ Oliver Bearman, Racing Bulls’ Isack Hadjar, Sauber’s Gabriel Bortoleto and Racing Bulls’ Liam Lawson.
Alpine’s Pierre Gasly, who had qualified eighth, suffered a water leak before the start and had to start the race from the pit lane two laps behind.
Lewis Hamilton’s difficult weekend continued for Ferrari. He was passed by Mercedes’ Kimi Antonelli just after half distance, by which time he was already complaining that his rear tyres were losing grip. He finished 15th.
