The former Hearts defender has impressed during a trial at Murray Park and could become the Gers' latest summer recruit.
McCoist said: "He's a very fit lad, he claims he's a little bit ring-rusty, which I appreciate.
"However, when you look at where we are and where we were last year and look at the level of Marius, who has played in the top league for the last seven years and was certainly one of Hearts better players, then I think it's safe to say he wouldn't look out of place in our team.
"It gives you options as well as another headache perhaps.
"The centre-half position last year was problematic for us and I'd imagine it will be the same for us this year in the league.
We feel that the opposition's best chance of scoring against us would be from set-plays.
"They certainly were last year and it was a little bit of an Achilles heel, we lost over 80% of our goals from set-plays.
"Bilel Mohsni, Jon Daly, someone like Zaliukas, Lee McCulloch in there will do their best to fend them off."