"I think it is important that Tomas plays in his natural position; he has done very well at right back but we haven't had a lot coming down that side offensively and I hope Robbie is going to come in and resolve that," he says.
"Tomas will put some competition in or secure a place in that centre half position."
As for the injury situation ahead of Cardiff, Alan adds:
"Jermain has got a sore ankle, but I am hoping he is going to be okay, and, apart from him, I think Ian Pearce is going to be available - which is a real bonus because obviously we have got Tottenham on Wednesday, for which Tomas is suspended.
"Kevin Horlock might be back training on Monday so there is some good news on that front and suddenly with the 11 outfielders I put on there is going to be five subs on the bench that are going to be really top quality as well - and that is what we should have at West Ham."
Tomas, of course, played centre half on Wednesday against Nottingham Forest following the signing of this week's other recruit, Hayden Mullins, who slotted in there.
"I think Hayden Mullins did us a real favour by filling in at right back and I am eager to put him in his real position; I wanted to bring in a right back and now I have done that in getting Robbie," he says.
"I think it gives us a chance for competition at centre half with Tomas, Ian Pearce, and Christian Dailly going for those two slots, and getting a bit of competition around the squad will hopefully equate to better results.
"Ian Pearce was out on Wednesday so doing what I did was the only option I had, really; I could have put Hayden at centre half where he has played for Palace a number of times, but I just felt he would actually offer us more down the side and I think, on reflection, he did okay.
"He had signed only that day and after being at Palace for eight to 10 years it was a big transition for him, but, as I said, he is one of the few players that could have carried that whole day off.
"Although it was an unfortunate slip over for their goal when he wasn't sure of his footing, he changed at half time and with the rest of the team did very well in the second half.
"I think he has been underperforming at Palace and that there is a bit more to come from him - I hope he will bring some energy to the midfield.
"We have reviewed the game and there were 31 crosses in it, which really should be enough to win any game at this level.
"But we can't seem to get that second or third goal which would give us a bit of a cushion or, more importantly, a win.
"The opposition made it very difficult, they played terrifically as well, and as a neutral you would have to say that it was a good game of football - but of course we are all West Ham fans and we wanted our team to win.
"Their position doesn't reflect how good they are in the league and they were coming off the back of a 6-0 win, so their confidence was high and it wasn't the best time to play them.
"In terms of the amount of time I had had to work with the team, and the application of the players, we did very well, though.
"The game never got stretched, never got opened, and that was a testament to both sides' work."
As for the numerous penalty appeals, Alan adds:
"I thought in the first half there was a definite handball which stopped the ball going to David Connolly who could have scored, and in that circumstance I think it should have been given - but you could argue it wasn't intentional.
"We just had a couple of chances where we were really unlucky, I thought; there was one incident when the defender just got a toe to it right off of Hutch's head into the keeper's hands.
"So they had their fair share of luck but so did we in the end when Paul Hart made a couple of substitutions and turned the game in the last five or 10 minutes towards their favour."
As for Don Hutchison's performance following his restoration to the starting line-up, he adds:
"This is a player of great quality; you look at Michael Carrick and Hutch and you have to say their fitness levels are not what I want - we are trying to get them through games at the moment.
"Once we get this midweek games out the way I can get into those two and get them up to speed, and if we can get them anywhere near the levels they should be then we have got a very good side on our hands.
"I thought in the first half Hutch did very well and used his great wealth of experience for us.
"Nottingham Forest are a team that keeps the ball away from home as a rule; they take the sting and tempo out of the game because they keep it so well.
"But we stopped that and did that part of the game really well, though creatively we wanted a bit more than we showed, especially in the first half."
Looking ahead the trip to Wales, Alan says:
"The record is good away from home; we are going into a hostile environment; you have to deal with that first before you take on the team and you have to have strong characters and a strong mentality to win at somewhere like Cardiff.
"We have shown that already in the cup, but I think it will be a little bit more hostile than that cup game so let's hope we are up for it - I am sure we will be.
"A win would be important now and put us right up there."
He has studied the video of the Carling cup game there and says:
"The first half wasn't going particularly well then we nicked a goal just before half time and then played some really great stuff.
"Trevor did really well at half time to get the game turned around and Defoe in particular had a really big night."
Let's hope he is fit enough to have another...