Jenson Button fears it might be hard to overtake in the Abu Dhabi Grand Prix even with two DRS zones available this year.
The McLaren driver held provisional pole for a short time near the end of Q3 before he was pushed down to third by Red Bull's Sebastian Vettel and the other McLaren of Lewis Hamilton.
Last year's race saw a famous lack of passing, frustrating pre-weekend championship leader Fernando Alonso's title bid. There were hopes that DRS and Pirelli would bring more action to Yas Marina, but Button suspects he will have to rely on pit strategy to try and make forward progress.
"I think it is going to be tough to overtake with DRS," Button admitted. "Hopefully, we will have a different story tomorrow in the race, we will have to see, but [the DRS zone] does feel short here.
"Yesterday I was using the DRS doing Turn 7 to Turn 8 and still could not overtake anybody. Hopefully there will be possibilities. It is a long, long race, with a couple of pit stops that are important to get right.
"We don't know what is going to happen with the tires – but we know more than Seb, obviously."
Button was pleased with his qualifying time in the end, saying his car had a few minor handling problems during the session.
"All weekend I have been reasonably happy with balance but still feel there is more to get from the car," he said. "I'm trying to find it, but was struggling with a nervous rear end. I tried a few things before qualifying, and at the start of qualifying it felt a bit better.
"During qualifying I found myself with massive bits of understeer, then tried to put more front end on the car but ran out of options. I'm quite happy with the lap and happy with the improvements we have made. In qualifying, there is not so much you can change."
McLaren was quickest in all three practice sessions, but Button said he was not surprised that Vettel had still come through to take pole.
"We have seen it before, we're very quick in practice, we are working through our program," said Button."It is not about being quickest during the day, it is just the way it happens. We run a different program, we've seen it before and we expect RBR to be quick.
"We feel we are more competitive and can challenge them in the race more than qualifying."