Rangers have clinched the signing of Michael O'Halloran from St Johnstone.
The wide player has signed a four-and-a-half-year contract after Rangers succeeded with a third bid understood to be worth a potential £500,000.
The 25-year-old told his new club's official website: "I am happy it is finally over the line because it has been a long time. I've not known whether I am coming or going over the last month but I am delighted to be here now.
"When you hear of the interest though your immediate reaction is that you want to go to the big club and I am just happy the opportunity has finally come and the move has happened."
The Light Blues faithful have already seen what O'Halloran is capable of after watching him torment the Ladbrokes Championship leaders in a League Cup tie back in September.
He created Saints' first goal in Govan before racing away from new team-mates Danny Wilson and Rob Kiernan to score the third goal in a 3-1 win.
And Warburton admits it was that display which convinced him he was good enough to star for his promotion chasers.
He said: "We always look to analyse teams before we play them. We played St Johnstone and we felt their threat came from O'Halloran's pace, whether it was central or wide.
"So from that point we were very aware of him after that match.
"We had him watched numerous times. We did our homework on his character and everything else. Everything that came back suited Rangers."
It appeared Rangers – who have already lost out on moves for Hibs' Scott Allan and Toumani Diagouraga, now at Leeds, this term – had been foiled again when St Johnstone rejected their first two offers earlier this month.
O'Halloran was even left out of the Saints side which took on Hamilton two weeks ago after McDiarmid boss Tommy Wright admitted his player had been unsettled by Gers' interest.
But the former Bolton youngster insists he never feared his dream move would not go through.
O'Halloran – who was on Celtic's books as a teenager – said: "I'm delighted to be here. It's been a stressful few weeks but I'm buzzing to have got across the line and now I'm looking forward to getting started.
"Tommy pulled me out of the Hamilton game and I thought it might go through that weekend. I ended up staying for two more games but as a professional footballer you have to be ready. It was hard trying to deal with the speculation but I think I coped pretty well.
"I can't thank Tommy Wright and the guys at St Johnstone enough for the opportunity they gave me after leaving Bolton. It was a great two years for me, especially winning the Scottish Cup and playing in Europe.
"However it was time to move on and when Rangers came in, the only thing in my mind was that I wanted to go and progress. Now my whole family is delighted I've got a move to such a big club.
"There's always a part of you that thinks it is or isn't going to go through. But I was always confident it would.
"I'm looking forward to the challenge of going for the title. It's two good sides with Rangers and Hibs competing and hopefully we can push on and claim our place in the top flight."
Warburton added: "I'm delighted. Michael fits the profile we want in a player perfectly. He gives some maturity even though he's still only 25.
"He has the experience and quality of having played at Premiership level. He's pacey. We want players with the flexibility of position so Michael ticks all those boxes. I think it's a great move for the club."
The Englishman, though, admitted he was "bemused" by reports suggesting midfielder Nicky Law would be used as a make-weight for the O'Halloran deal.
However, he is pleased with his January business.
Warburton – who has also sanctioned the signing of Mekhi McLeod from Wolves for the club's Under-20s side – said: "That's us done. Harry has come in as well as the keeper Maciej Gostomski so we're delighted. Michael too is a big piece of business for us.
"We're a tight, lean squad but I'm delighted with that. I think you do more damage in January by bringing in too many players because you destory the unity and harmony of the dressing room.
"I look at the bench for tomorrow's game against Raith and it's the strongest I've had since been at Rangers."