Achilles tendon rupture
On 8 June 2010, he signed a new one-year deal. Robertson went on to make a total of 23 appearances that season in Chesterfield's 2010/11 League Two winning campaign, enjoying a successful spell at centre half for much of it. However, he suffered an Achilles tendon rupture away to Hereford United in April, ruling him out for the last few games of the season and much of the next.