United are still without an away win in 2007 as a late penalty secured victory for Crystal Palace in Saturday's Championship fixture at Selhurst Park.
Ben Watson struck home from 12 yards after Chris Morgan was pulled up for a foul on Tom Soares with 89 minutes gone.
After a dull first half, a Mark Hudson own goal gave the Blades the lead before Soares and Carl Fletcher put Palace ahead. Beattie poked home his seventh of the season and it looked enough to earn United a point until the penalty.
Robson handed loan newcomer Cahill an instant debut, alongside skipper Morgan in the centre of the defence, and Montgomery was a surprise inclusion in the midfield - less than three weeks after a hernia operation.
Cahill, who emerged last out of the tunnel, was quickly acquainted with Dickov as the striker, unsurprisingly, committed the day's first foul.
Following a slow start, Fletcher smashed the game's first effort well over on nine minutes and then Kenny gathered under his own crossbar after Scowcroft had won Green's diagonal cross. The first two United attempts - on 17 and 19 minutes - were both on target but comfortable for Speroni. Stead cut in from the right for the first effort and then Tonge hit the second, after a quick break out of defence.
Cort rose highest and headed just wide at the back post from Green's free-kick on 22 minutes and before the half-hour mark Palace went close again. Naysmith conceded a corner to prevent Soares getting on the end of Watson's inswinger and from the resulting Green delivery, Kenny watched on as Scowcroft headed over.
United finished the half the stronger, giving hope to the fans that made the long trip to south London. On 37 minutes Gillespie and Armstrong linked up on the left with the latter delivering a deep cross which Beattie met but couldn't keep down.
The final chance of the period - on 42 minutes - saw Gillespie run at the Palace defence but despite his long-range shot taking a deflection, Speroni gathered in at the second attempt.
United's improvement at the end of the first half was rewarded at the start of the second - albeit with a little help from the home side. Beattie won a corner from Cort and Gillespie's inswinger was sliced into his own net by a Palace defender. Under pressure from Cahill, the ball ballooned off HUDSON's shin and beat Speroni, via the crossbar.
Both sides swapped penalty appeals - Morgan on Dickov and Hudson on Stead - but the referee waved play on. The decisive moment, as far as Palace were concerned, however, was the arrival of Freedman.
Within five minutes of being introduced, the experienced Freedman carved open United's defence by laying off to the right for the unmarked SOARES to rifle past Kenny from ten yards.
The Blades had a chance to restore their lead within 60 seconds but Gillespie's volley from Stead's cross was over before Palace went back on the offensive. With Bromby dragged out of position, Dickov sliced an effort wide.
Beattie attempted a header at Speroni but was unable to get enough power and then, with the next attack, Palace took the lead. Craig's cross from the left looked comfortable for Kenny but Bromby edged the ball on and FLETCHER was gifted the easiest of tasks of turning the ball home at the back post.
Stephen Quinn replaced Gillespie on the right and although United's leveller came from that flank it was Bromby's forward ball which caused hesitation in Palace's defence and BEATTIE beat the goalkeeper in a race and accurately toe-poked home from the edge of the box.
Robson went looking for the victory, throwing Webber on at the expense Bromby, but it was another of Palace's substitutes - Idrizaj - that caused the next problem for United's defence but Cahill did well to chest clear from the line.
However, just as at Blackpool in midweek, there was late drama. With 89 minutes gone, after a Craig cross into the box, Morgan's header was blocked and the skipper was then adjudged to pulled down Soares as they looked to pounce on the loose ball. Despite the protests, the penalty was given and WATSON beat Kenny with a powerful effort into the corner.
In the five added minutes, United could only force one more worthwhile effort and that came after Cort fouled Stead on the edge of the box. Beattie took responsibility for the free-kick but Speroni did well to hold the powerful effort.
The Blades attempted a number of hopeful balls into the Palace box but were unable to breach the home side for a third time, leaving Robson still chasing his first away win.
Palace: Speroni, Craig, Hudson, Cort, Fletcher, Scowcroft (Idrizaj 85), Watson, Soares, Butterfield, Dickov (Dickov 83), Green (Freedman 55).
Unused: Flinders, Lawrence.
Blades: Kenny, Bromby (Webber 79), Naysmith, Morgan, Beattie, Stead, Montgomery, Tonge, Gillespie (S. Quinn 74), Armstrong, Cahill.
Unused: A. Quinn, Lucketti, Sharp.



















