Two-time F1 World Champion Mika Hakkinen has claimed McLaren will emerge as Red Bull's nearest challengers despite a slow start to the season.
The Woking-based team endured a nightmare season-opener in Bahrain and has since secured only 17 points in the next six races to sit sixth in the Constructors' standings.
McLaren's hierarchy has been consistent in urging patience with a number of infrastructural improvements set to be completed and ushered into operation this year, as well as an influx of technical personnel including David Sanchez from Ferrari and Rob Marshall from Red Bull.
Marshall's former employer has been dominant in the opening seven races, securing a race victory in each and only missing out on pole at the Azerbaijan Grand Prix, where Charles Leclerc qualified fastest for Ferrari.
But despite the gap between Red Bull and McLaren covering enough to accommodate four other outfits, Hakkinen believes his former team will emerge as a shock contender.
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Surprise us massively
On how Red Bull has asserted its dominance, Hakkinen told Unibet: "When we look at the teamwork, for example, their pit stops take two seconds, other teams change their tyres in three or four seconds.
"It shows the spirit of the team, it shows the energy and teamwork they have.
"It is not easy for the other teams to catch up. I don't think anyone is able to catch up [to Red Bull] this year.
"The only surprise I think we'll see is McLaren's possible progress during the next two months.
"I think they will surprise us massively, just in terms of the speed of the car. They will probably challenge Red Bull."