Rangers manager Mark Warburton still hopes to make two new signings before the transfer window shuts despite failing to secure his major targets.
Midfielder Toumani Diagouraga joined Leeds United from Brentford instead, while St Johnstone have rejected two bids for forward Michael O'Halloran.
"We hope to get one or two in," said Warburton. "Sometimes they happen quickly. Sometimes they take more time.
"We are getting there, making progress."
Rangers are five points clear at the top of the Scottish Championship, but second-placed Hibernian have made the most eye-catching signing so far ahead of the window closing on 1 February by taking Republic of Ireland striker Anthony Stokes on loan from Celtic.
But Warburton expressed his faith in managing director Stewart Robertson and head of football administration Andrew Dickson.
"Sometimes the deals just take time," the manager added. "January is always more difficult for a number of reasons.
"But Stewart Robertson and Andrew Dickson do a lot of work in the background and hopefully we will get something over the line."