McLaren has reportedly ousted its technical director Tim Goss.
The news follows a difficult start to the 2018 season for the once-great British team.
Hopes were high after the switch from Honda to Renault power, but McLaren remains conspicuously low in straight line speed.
"Last year we all thought the chassis was excellent and the problem was Honda," said former Renault technical boss Pat Symonds.
"But now they’re only the third best Renault team. We’re hearing now that the late change from Honda to Renault delayed the work and we’ll only see the true McLaren in Spain.
"If they really do take a big step, great. If not, they’ll be answering some very unpleasant questions," Symonds added.
When asked about the ousting of Tim Goss, a McLaren spokesman was quoted as replying: "We are currently looking at how we can position ourselves to become successful again.
"We’ll talk more about that soon but until then will not make any further comment."
Goss had been at McLaren since 1990.
Fernando Alonso, whose world sports car adventure begins next weekend, said in Baku: "This year, we hoped to get close to the podium, but we’ve found that we are a bit far away from that."
And teammate Stoffel Vandoorne told RTBF broadcaster: "There is a little bit of pressure on the team because the results aren’t at the level we want.
"But it’s positive. Everyone understands the challenge and so I hope we will see progress in the next races."