<text>  Newcastle owner Mike Ashley has admitted his failure to invest in the squad in January has left them desperately short of cover as they prepare to face Arsenal with just 13 senior players. Head coach John Carver appeared for Thursdays pre-match press conference with a 4-4-2 line-up of players unavailable to him. It read: Rob Elliot thigh; Paul Dummett knee, Fabricio Coloccini suspended, Steven Taylor Achilles Massadio Haidara knee; Rolando Aarons hamstring, Cheick Tiote knee, Mehdi Abeid thigh, Siem de Jong lung; Papiss Cisse suspended, Facundo Ferreyra back. John Carver revealed that Mike Ashley regrets not investing in the squad in the January transfer window . The Newcastle owner didnt invest in January despite sanctioning the sale of Davide Santon . And Carver says he has been left in a difficult position after Uniteds hierarchy Ashley and managing director Lee Charnley decided to allow defenders Mapou Yanga-Mbiwa and Davide Santon to leave the club in January without bringing in replacements. The fact that Lee and Mike have acknowledged that we are paying the price for not strengthening the squad doesnt make me feel better, but at least people understand thats what has happened, said Carver, whose side have won just one in six since the close of the window as he bids to win the job on a permanent basis. Now whether it was me or Alan Pardew, if he was still here, that would be the same situation. Mike Williamson and Daryl Janmaat centre right are the likely pairing for the upcoming Arsenal match . Captain Fabricio Coloccini left was sent off for a reckless lunge and will miss the next three games . I have got to deal with that situation and I will. What I wont do is give up on it, I wont think, Well, Ive got all those people out, thats it, thats me done, Im not going to get this job. And Carver says the board have already made assurances of significant investment in the summer. The squad needs to be stronger and they have acknowledged that to me - they know they have to invest, he said. I have been part of it in the last few weeks and there are things in place. Thats from the top. Theyve got to do something about it, and they know that. Mapou Yanga-Mbiwa right is someone Newcastle could do with but he was sold to Roma in January . 