The Fiorentina defender is currently in talks with the Club and the Hammers boss is hopeful that a deal will be concluded soon.
"Just as it was with Don Hutchison, these things are not done overnight and you have to be patient," says Glenn, "and that is what we are doing with Tomas.
"We are now very close to getting his signature and I will be very pleased when we can bring this one to a close as well.
"But it is more difficult when you sign someone from abroad and there is obviously a lot of paperwork going between us and Fiorentina at the moment.
"We are as close as we have been to signing him. It is probably going to be difficult, though we are doing everything we can to get him into the team for Saturday."
Glenn hopes that Tomas can be as big a succcess as his last big signing has so far been, and he explains: "I have been very pleased with Don's two performances so far; he did very well at Derby and the longer the game went on the better he did.
"He was probably our best performer at Reading and the partnership of Don, Michael Carrick, and at times John Moncur in the centre of the field will be good for us."