The Scot, who this week signed a contract extension at Fulham, was heavily linked with a move to Teesside in the January transfer window, with the former Leeds United forward reportedly keen to return north.
But Fulham dug their heels in and refused to entertain the prospect of McCormack leaving, with Boro, in the event, having to concentrate all their energies on successfully pursuing Jordan Rhodes.
The ex-Blackburn striker is likely to line up for the visitors today in direct opposition to McCormack in a juicy subplot.
Boro’s head coach Aitor Karanka says they along with David Nugent and Derby’s Chris Martin provide the Championship’s best four strikers – although the likes of Hull City’s Abel Hernandez and Burnley’s Andre Gray would query their omission.
On whether he rates McCormack as the most potent striker at a rival club, Karanka said: “Yes. I like McCormack and I like (Chris) Martin from Derby also.
“Apart from Jordan (Rhodes) and David (Nugent) – who are the best two – third and fourth can be Ross and Martin.”
McCormack fired a hat-trick in a helter-skelter 4-3 win over Boro at Craven Cottage on the penultimate weekend of the 2014-15 season to end the Teesside club’s hopes of automatic promotion.
The Spaniard added: “Ross has been scoring goals for I don’t know how many years in a row. He is not alone because they have good players like (Mousa) Dembele.”
On the possibility that last month’s link with Boro could affect his performance on Saturday, Karanka added: “I don’t know Ross (but) I have been here for two years and when I have seen him on the pitch, I don’t think he will be affected by something like the talk in January.”
Last six games: Fulham LDWLWD, Middlesbrough LLDDDW.
Referee: C Breakspear (Surrey).
Last time: Fulham 4 Middlesbrough 3; April 25, 2015; Championship.