Barcelona circuit officials had to close the entrance to the spectators grandstand facing the McLaren garages today, after local fans were constantly howling abuse at the Woking outfit.
Spanish fans, believing their hero Fernando Alonso was treated unfairly by the team last year, have continually expressed their displeasure with McLaren both at Valencia and Barcelona in preseason testing.
This included shouting of profanity at Alonso's 2007 teammate Lewis Hamilton, hanging unflattering banners, and even throwing junk towards the McLaren cars as they left for the track.
Initially, the Barcelona track organisers sent security guards to the grandstands while McLaren team members did their best to ignore the abuse.
However today, following another escalation in the fans' behaviour, the team asked the track officials to shut down the entry to that specific grandstand in order to get on with their work undisturbed.
A source at the Barcelona circuit told autosport.com this involved "a minority of fans that were behaving unsportingly and tarnishing the reputation of the Spanish fans, who simply come to the track to follow the sport they love."
Asked about the situation, a McLaren spokesman told autosport.com: "Vodafone McLaren Mercedes has raced and tested on Spanish circuits for many years, and everyone connected with the team regards Spain and the Spanish people with great affection, Lewis included."