But the deal has some way to go with the Scottish champions seeking around £2.7m for a player who moved to Ibrox from Hibs in 2007 for £2m.
Thomson played a major part in Rangers retaining the title, figuring in 25 of their 38 league games.
The 25-year-old is entering the final year of his contract and the Gers are prepared to listen to offers for the player capped twice by his country.
With Gordon Strachan also chasing Dundee United winger Craig Conway and Hearts' creative midfielder Andrew Driver the pressure is on Boro to offload high earners such as Mido, Didier Digard and Marvin Emnes.
After sealing deals for Kris Boyd and Nicky Bailey, the Boro hierarchy revealed they expect to make further inroads into the transfer market over the next fortnight, with talks over a proposed deal for Celtic centre-half Stephen McManus advanced.
Strachan has handed Boro chief executive Keith Lamb a list of his targets as he seeks to add a steely spine to the side that struggled to establish itself in the Championship last season.
We are doing a lot to bring new players in. Keith is the man with all the pressure on right now and I can sit back and do the coaching, said Strachan.
We want to bring in players with drive, real characters.
Look at Blackpool last year. I think every one of that team had a knock back in life somewhere along the line and that's given them the drive to prove to themselves that it wasn't all about losing in their careers.
That drive is what we are after. We want to mould a group that respects each other and enjoys the up and down of the season.
The Scot defended his record of targeting new recruits from his homeland, adding: If you look at any manager who spent certain time in a league he signs players from there, so Arsene Wenger has a lot of Frenchmen, Liverpool have a lot of Spanish people there and Man City they are from everywhere!
You learn more about people you play against them than you do about your own players. You look at people like (Blackpool's) Charlie Adam who didn't set the place on fire in Scotland but he was an absolute star in the Championship.
He and (West Brom playmaker) Graeme Dorrans were some of the best players in the league last season. Scotland is a great breeding ground for people.
Source: Northern Echo
Source: Northern Echo