Trackside operations director Alan Permane confirmed that the wing was at fault, although the team had yet to isolate exactly what the problem was.
"We don't know what it is, there is nothing obvious but it went away when we changed the wing," said Permane.
"After his first pitstop, you just see it go on the aero data.
"He lost 20 points of front downforce, so we had no choice but to change or he would have gone backwards.
"We put him on the options, put a new front wing on because you never know, if there was a safety car he could do some overtaking later on."