Captain Mark Hudson insists Cardiff City's labouring 2-1 defeat at Doncaster Rovers is a reality check for his Championship high-fliers.Boss Dave Jones was furious with his Bluebirds as they suffered their first loss this season against the previously winless Doncaster at the Keepmoat. [LNB]And for this first time this term, the division's top-scorers failed to score. [LNB]"We must use this defeat as a reality check, we have to work hard and learn from it," Hudson told BBC Sport. [LNB]Cardiff were chasing their fourth successive win but Jones bemoaned his Bluebirds' lack of work-rate as the leaders dropped to second with their first loss at Doncaster since 1951. [LNB]Jones has told his lacklustre players to use the Doncaster defeat as a "wake-up call" as he hopes the cloud ultimately has a silver lining. [LNB]Hudson, who replaced Joe Ledley as City skipper in the summer, has promised his team-mates will watch the Keepmoat video nasty to ensure the Welsh team lose the lessons from their Doncaster disappointment. [LNB]"Things never go smoothly through the season but we're very disappointed that this performance has come so early.[LNB] Away from home, this is where we need to pick up points Cardiff City striker Kelvin Etuhu "We will have to train hard, watch the video of the game as we want to put it right and change that." [LNB]Hudson and his Cardiff colleagues are frustrated that they have not got another Championship game for more than two weeks to make amends for their woeful display at Doncaster. [LNB]But the Bluebirds will have to dwell on their disappointment over the international break until Sunday, 13 September when Jones' men host Newcastle United in what could be the first full house at their new Cardiff City Stadium. [LNB]"We now have a couple of days to go off and think before we come back for training," said Hudson. [LNB]"We wish we had another game straight away in midweek to get this defeat out of our system." [LNB]Cardiff had scored 11 league goals - plus six more in the Carling Cup - before their trip to the Keepmoat while their backline has been one of the Championship's meanest, conceding just two goals. [LNB]Doncaster, on the other hand, were previously without a win and had scored just twice in their first four league games. [LNB]But the hosts shocked Cardiff as Adam Lockwood and James Hayter had fired Doncaster in a two-goal lead in the opening 17 minutes - and there was no way back for the previously free-scoring visitors.[LNB] After just getting back from a long trip to Doncaster, I can honestly say that we simply didn't turn up today HertsBluebird And Hudson admitted: "Defensively I don't know what went wrong but their movement was too good for us in the first 20 minutes - we weren't ready for that. [LNB]Jones was annoyed with his players complacent attitude as he lashed-out: "Players' ability will always be there but if you don't put the work in - and some of them didn't put the work in - it won't always work out." [LNB]New signing Kelvin Etuhu, who replaced Jay Bothroyd when he went off injured in the eighth minute, thought that if Cardiff are to make a concerted push for promotion, they should be winning at places like Doncaster. [LNB]"The lads are very disappointed as they are not very happy with the team performance, " said Etuhu. [LNB]"As away from home, this is where we need to pick up points. [LNB]"In the first 20 minutes we gave the game away as they scored from set plays and you can't afford to switch off in this league."