Middlesbrough looked the more threatening in the early stages amidst a real cup-tie feel to the game.
Some sustained Addicks pressure at the end of the first half led to some frantic Boro defending at the start of the second period.
The home team will probably be the more rueful after carving out the best chances of the last-eight tie while restricting Boro to just a handful of chances despite the visitors seeing plenty of the ball.
Charlton starting line-up: Chris Powell, Matt Holland and Shaun Bartlett all started so Spector, Euell and Rommedahl dropped to the bench. Jay Bothroyd returned in place of Sorondo among the substitutes.
Alan Curbishley: "I knew tonight was going to be a tight game. I asked the players to make sure they kept our season going and they did. Although we had our opportunities in the first-half and we needed to take one of them it was a very good performance. The game fizzled out a bit, but both teams went for it with their substitutions near the end."
Steve McClaren (MFC): "Charlton opened us up and we came under a lot of pressure in the first half."
Source: Official sites