Cardiff City jettisoned Callum Robinson and Mahlon Romeo from their squad for the win over Birmingham City over disciplinary issues, manager Erol Bulut has revealed.

Cardiff named only 19 players in their matchday squad for the game at St Andrew's, one fewer than their opposition. While the likes of Callum O'Dowda, Jak Alnwick, Mark McGuinness, Kion Etete and Josh Wilson-Esbrand were known to be injured, questions were asked about Robinson and Romeo, both of whom were named on the bench for the defeat by Hull City at the weekend.

And when asked whether the duo were missing through injury, Bulut replied: "No, they are not injured. It's a disciplinary penalty from my side.

"We don’t need to speak about this. It is internal that we cleared it. I spoke with the player. I said at the start of the season, discipline and respect are the most important things for me. They were a little bit away from that. That's why they were not with us."

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Both players were big players during the relegation-fighting season last year, but have found themselves out of the team for a number of reasons this season.

Robinson has had injury issues, but is also unlikely to displace the likes of Aaron Ramsey, Rubin Colwill or David Turnbull Cardiff's starting XI. While on the wings, Karlan Grant and Josh Bowler have been nailed-on favourites.

Romeo has fallen foul of Cardiff changing formation this season, meaning Perry Ng, one of Cardiff's most consistent performers and the reigning player of the year, has had a free run at that right-back spot, with no wing-backs having been deployed.

Nevertheless, Cardiff's injury list is lengthy and Bulut would have been loath to narrow his options further, but felt it necessary to take disciplinary action over something which clearly occurred between the Hull game last Saturday and the Birmingham game on Wednesday. When asked about the nature of the indiscretion, Bulut declined to divulge further information.

Cardiff travel to Millwall on Saturday, another team fighting for their lives at the bottom of the table, just like Birmingham. Bulut confirmed that Romeo would be back but further conversations would be had with Robinson.

Asked if their disciplinary penalty was just for the Birmingham trip, Bulut said: "For Mahlon, yes, for Robbo, no. We will see. We will have to have discussions about that.

"We will have a talk with [Romeo], but he will be back (for Millwall)."

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