Third Round. He started the 2010–11 season by scoring Doncaster's first goal of the season in a 2–0 win over Preston North End at Deepdale. He went on to make 37 starts despite an injury hampered season, with one of the highlights being his second goal of the season against local rivals Scunthorpe United in a 3–1 win at Glanford Park. O'Connor continued to be a vital part of the Rovers team until he lost his first team place a few months after Dean Saunders took charge of the club in September 2011, and watched from the sidelines as "Donny" were relegated out of the Championship in last place in 2011–12. Derby County On 1 August 2012, O'Connor joined Derby County for an undisclosed fee, signing a two-year contract with an option for a further year. O'Connor made his debut at Pride Park in a 2–2 draw with Sheffield Wednesday on 18 August, coming on for Nathan Tyson as a 74th-minute substitute. He made his first start three days later, in a 2–0 defeat to Bolton Wanderers at the Reebok Stadium. Two days after the Bolton match, Derby manager Nigel Clough praised O'Connor by saying; "With only two [league] games played this season, we've seen the value of James already. He can play anywhere across the back four and he just slots in with no fuss whatsoever. He's a good, competent Championship player and there aren't too many about like him who can come in and do a job in so many positions; he's a very good and important player to have in the camp." He scored his first goal for the "Rams" in a 2–0 home win over Barnsley on 6 November. O'Connor covered at left back for the injured Gareth Roberts in December 2012, after he fell behind Jake Buxton and Mark O'Brien in the pecking order in central defence. In February 2013, it was reported that O'Connor had picked up a knee injury. In March, he returned to full first team training, with a scheduled return to the match-day squad for Derby's game on Good Friday, 29 March. However, he did not make a first team appearance before the end of the campaign, and ended the 2012–13 season with 23 appearances. In May 2013, O'Connor was informed that he would not figure regularly at Pride Park during the upcoming 2013–14 season, and he was allowed to look