Despite a spirited performance, Colchester United's FA Cup dreams were shattered in unspectacular fashion at Bramall Lane.
Sheffield United needed the old heads of Alan Wright and Paul Peschisolido to kill off the brave second division outfit.
The two 32-year-olds combined on 61 minutes, Canadian Peschisolido heading home Wright's free-kick at the front post.
But Colchester, famous for knocking out the great Leeds United 33 years ago, enjoyed the lion's share of possession and gave a good account of themselves.
Phil Parkinson's men started brightly, pinning their first division opponents in their own half. They proved resolute also at the back, captain Karl Duguid heading clear from just off the goalline under pressure from Peschisolido on ten minutes.
Sheffield created the better chances through the quick feet and quick thinking of Peschisolido. Twice he unselfishly squared to Wayne Allison and Phil Jagielka, who fluffed simple opportunities to give Sheffield a first-half lead.
The second division side's best chance came just after half time when Rowan Vine, the hat-trick hero in the last round against Coventry, bore down on goal. But the on-loan star took a touch too many and Rob Page recovered for Sheffield.
Peschisolido struck just after the hour, heading home Wright's free-kick, to register his ninth goal of the season.
Colchester goalkeeper Simon Brown then kept his side in the tie with a crucial save to deny Peter Ndlovu from close range in the 64th minute.
Eight minutes later Brown denied Ndlovu again before Kem Izzet fired a 20-yard effort just wide of Paddy Kenny's upright, after good build-up play from the U's.
Peschisolido continued to be the biggest cause of problems for Sheffield, but he was thwarted again by Brown.
Colchester threw men forward at he end, but couldn't force a replay.