Lando Norris says McLaren knew their Belgian Grand Prix was going to be tougher this year compared to previous years, explaining why the racing was "a lot worse" at Spa-Francorchamps.
After being part of the group of drivers who took power unit penalties, the McLaren driver started the race from 17th on grid.
Norris made his way through the field in the early stages of the race, but later found himself at the back of a group of cars who were stuck behind the Williams of Alex Albon, who had strong straight-line speed.
He was ultimately unable to break into the points, crossing the line in 12th at the end of a race where overtaking proved difficult.
"I think we knew the racing was going to be a lot worse here this year than it was the previous years, just because the slipstream [was] so much worse," Norris told media, including RacingNews365.com.
"Apart from that, just getting stuck behind the Aston and the Williams.
"The Aston's pace was better than ours today, but the Williams is just so quick in a straight [line] and I'm in the DRS train, so I couldn't do a lot."
McLaren reverted to different rear wing for Ricciardo
Norris' teammate, Daniel Ricciardo, also had a tough race finishing in 15th, despite initially starting from seventh on the grid.
The Australian said the team had to revert to a different rear wing on his car because of an issue they found with their race-spec.
That caused him to suffer from more drag, which hampered his efforts to progress.
Ricciardo said: "We simply just weren't quick on the straights; we had to put a different wing on because our race spec one had a had a bit of an issue.
"So I knew today was probably going to hurt us on the straights, just with more with more drag. I don't think I was the only one struggling to pass on the straights.
"I had speed to use in the second sector, but then the first and third, even with DRS, I just couldn't pass, so [it was a] pretty long and frustrating race."
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Ricciardo: We were waiting for a mistake from others
As he was stuck in the same train of cars as Norris, Ricciardo felt he was waiting for a mistake from the other drivers as he struggled to get close enough for an overtake.
He believes that while the new regulations enable closer racing, the tow effect from cars which enable slipstreaming on the straights is a lot smaller as a knock-on.
Ricciardo added: "I said on the radio, 'Yeah, honestly, I'm trying, but unless they make a mistake in front it's literally impossible to pass'.
"The good thing about this series is you can race closer, but the bad thing is the tow effect is smaller. So on a track like this, I felt like it made overtaking more tricky."
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