MIDDLESBROUGH will hold talks with Gary Caldwell and Barry Robson within the next 48 hours after agreeing a fee of around £1.7m with Celtic for the pair.

And boss Gordon Strachan has also lined up two more Bhoys – Willo Flood and Chris Killen – until the end of the season.

The quartet are due on Teesside over the weekend and Strachan expects to tie up the deals early next week, enabling them to join their new team-mates ahead of next Saturday’s trip to Sheffield United.

Strachan hopes there will be no late hitches with the permanent signings of Caldwell and Robson, having spent the best part of a month trying to convince Celtic to part with them.

However, in Caldwell’s case, the former Newcastle United and Hibernian centreback is also being tracked by Wigan and the lure of Premier League football could still prove decisive.

Strachan, however, remains confident his relationship with the 27-year-old will help to convince him the Riverside rather than the DW Stadium is the place to be, particularly how both clubs are offering similar wages.

Caldwell was taken to Celtic Park by the Middlesbrough manager in July 2006 and has since become a key member of the Scotland squad, earning 32 caps for his country.

He was going to leave at the end of his contract for nothing in June, but Strachan has managed to convince Celtic boss Tony Mowbray to part now.

Robson, a central midfielder, moved to Celtic from Dundee United for £125,000 two years ago and the 31- year-old was one of the better players in last week’s 1-1 Old Firm draw with Rangers.

The two other proposed signings are more surprising.

Both Killen, 31, and Flood, 24, were also signed by Strachan but have struggled to make an impact at Parkhead.

Target-man Killen, a New Zealand international intent on playing in the World Cup, has made just four SPL starts for Celtic in two-and-a-half years, scoring twice.

Flood, who started at Manchester City, only moved to Glasgow 12 months ago and has started just twice in the SPL.

Strachan has also been looking at bringing Scott McDonald, Mark Wilson and Stephen McManus from Celtic, but deals for those would now seem unlikely.