The loss of this recognised goalscorer is a tremendous blow even though Sunderland have just splashed out on Tore Andre Flo and Marcus Stewart.
There was no signs of comfort either from Sunderland's performance at the Riverside Stadium before a 32,000 crowd.
Middlesbrough were by far the superior side. There was more strength in defence, more flair in midfield, with two of their foreign stars providing the finish to round off a highly competent performance.
Middlesbrough manager Steve McClaren took a gamble in the summer when he signed Italian Massimo Maccarone, a comparatively unknown player with no experience in top flight football in his own country.
Yet Maccarone scored a brilliant goal and was involved in the two goals of Slovakian international Szilard Nemeth.
Sunderland had no-one to compete with the striking power of this pair.
Former Middlesbrough and Sunderland legend Brian Clough saw Middlesbrough take the lead after 16 minutes.
A Maccarone shot rebounded off goalkeeper Thomas Sorensen for Nemeth to pounce from close range.
After 37 minutes full-back Franck Queudrue sent over an accurate free-kick from the right to the far post where Maccarone sent a bullet-like header into the net.
Early in the second half there was a rare tribute to Middlesbrough chairman Steve Gibson.
A section of the home crowd chanted: "There's only one Stevie Gibson" - recognition for his £20million backing to team-strengthening in the summer.
The game was wrapped up with an excellent Maccarone-Nemeth combination in the 65th minute. Nemeth raced on to a superb through pass by Maccarone to chip the ball past Sorensen.
After the match a jubilant McClaren said: "A win is always extra special when it's a local derby.
"We scored at the right times. They were just coming back into the game on each occasion when we killed them off."
"We had plenty of the game but we were lacking in the final third of the field," said Reid after the game. "We lacked discipline and we were bossed about defensively. We have to go back to the basics."