As a transfer window, January is a strange one.
It is very difficult to bring in players who you really think are better than what you currently have, which is why I think that Neil Lennon and his staff have seen something they like in 20-year-old Australian Tom Rogic.
Having now signed Rogic on a four-and-a-half- year deal, Lennon will have the opportunity to fully appraise the highly-regarded player next to what he already has.
And that is where you tend to see whether or not it is worth moving for someone.
I don't know how much interest there was in the player and how much of it came down to his agent trying to sell the move, but the bottom line is that for £450,000 Celtic have bought a player with the potential to do well.
Rogic may not be in the same mould as the likes of Victor Wanyama, Beram Kayal and Gary Hooper, who all joined the club as relative unknowns but who were more or less seasoned campaigners by the time they arrived at Celtic.
But he is in keeping with a signing policy that has so far proved to be very successful for Celtic.
Rami Gershon fits into that too – he is someone who Celtic can take a look at between now and the end of the season and see how he fits into the team.
I don't think that January is the best time to be looking for players to come in.
Most players are tied to their clubs and don't necessarily want to move in the middle of a season. It can be hard trying to attract the right kind of player. Celtic's other business may now come in trying to prolong the deals of some of the current players.
As I said last week, I don't think it matters if Hooper signs an extension or not.
I don't imagine that he, or anyone else will leave the club before the summer so in that respect it changes nothing with regard to this campaign.
The re-emergence of Anthony Stokes following his lengthy lay-off with ankle-ligament damage may provide other options for Lennon.
And Mo Bangura also posted notice of his return from a loan deal with AIK Stockholm during the friendly win over Steaua Bucharest in Marbella this week.
Sometimes the least likely scenario can happen in football.
But for Bangura to become a genuine option for Lennon, I think, would still take a bit of convincing.
The player will feel all the better for having got his name on the scoresheet over in Marbella and with injuries and suspensions and a heavy fixture list, you just never know.
However, especially where the fans are concerned, I would imagine he would need to work pretty hard to win people over.
The situation with Stokes is a little different. For me, he is one of the most prolific scorers in the Scottish game.
Out of contract this summer, he isn't just playing for a new deal at Celtic that would likely be his first choice, he is playing for a contract, full stop.
It is in his hands now. He really needs to convince Lennon he deserves the opportunity to play.