Doncaster Rovers' management duo Sean O'Driscoll and Richard O'Kelly celebrated their 200th game in charge with a 2-1 win over visiting Derby County. The victory over the Rams saw Rovers equal their best unbeaten sequence of the season (four games) and move to within four points of the play-offs."There is always one team which comes with a late run and it could be us," said striker Billy Sharp, who gave Rovers the lead from the penalty spot."What a fantastic character Billy Sharp is," enthused Rovers No 2 O'Kelly."To step up and be as positive as he was after missing one at Preston in midweek, I can't praise him enough."I've been in his shoes when I was playing and I missed a penalty on the Saturday and also missed one on the Monday."Derby boss Nigel Clough wasn't convinced that it was a penalty.Argued O'Kelly: "From where I was stood it was a challenge from behind. "But we've had some games this season when there has been a similar challenge and we've not got a penalty."Having watched Rovers take an early lead, O'Kelly admitted that he would have liked to have seen another goal before the interval to underline Rovers first half dominance."You are always looking for a second and third goal after you've gone ahead," he said. "It was a bit like Preston the other night where we dominated the first half but didn't get the second goal."Our decision-making on the ball, regardless of the conditions, was very good. We also kept a very good team shape so if a move broke down we were in a good position to win it back and keep the attack going."The second half was scrappy to start with but we still looked very organised and we didn't give them a lot of opportunities to get back into the game before Jay Emmanuel-Thomas made it 2-0."It was a magnificent strike. He's got a wonderful first touch and he carries the ball well. The pitch doesn't help him but he copes with it better than most."I think that the way he has settled into the team in the last week has been first class. He has integrated really well."