The Wales defender, released by West Ham last month, featured as one of four Hoops trialists in last night's 13-0 friendly win away to Cornish amateurs Tavistock.
Chance to shine: Danny Gabbidon featured in friendly win
Gabbidon made just 92 appearances in an injury-hit six-year spell with the Hammers after leaving Cardiff, where he made 219 appearances and scored 10 goals.
Warnock told www.qpr.co.uk: 'We're just looking at Danny.
'I spoke to him last week and I told him to come to Cornwall - there's no pressure down there.
'He can come and train and we had a really tough session running yesterday morning. It also gives him the chance to look at us too.'
Another of the quartet of free agents, former Sheffield United and Portsmouth striker Danny Webber, was on the scoresheet in the rout.
Webber's two seasons with Pompey were largely unproductive, with his 50 career goals coming mostly in his previous spells with the Blades and Watford.
Webber played for Warnock at Sheffield United.
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