Middlesbrough had to work hard to beat Northampton and claim a place in the third round of the Carling Cup.
Rochemback fired home from 35 yards to open the scoring
Town went close when Ian Henderson hit the post with a diving header after Brad Johnson's shot was saved and Alex Dyer also went close for the Cobblers.
But Boro took the lead through Fabio Rochemback's superb 35-yard free-kick and then hit the bar through Seb Hines.
Northampton kept pushing forward but Dong Gook Lee's drove home a second goal before Mido hit the bar late on.
Middlesbrough: Jones, Young (Boateng 73), Davies (Hines 36), Wheater, Taylor, Johnson, Cattermole, Rochemback, Downing (Mido 70), Lee, Sanli.
Subs Not Used: Schwarzer, Craddock.
Goals: Rochemback 53, Lee 66.
Northampton: Bunn, Crowe, Hughes, Doig, Jones, Dyer (Brett Johnson 80), Bradley Johnson, Burnell (Aiston 66), Holt (Larkin 67), Hubertz, Henderson.
Subs Not Used: Dunn, Kirk.
Ref: Neil Swarbrick (Lancashire).