Brave Bolton battled right to the end against the reigning Premier League champions, but fell to a 2-1 defeat at Old Trafford.
An early own goal from Zat Knight and a second from Antonio Valencia gave Manchester United a two
goal advantage at half-time.
Matt Taylor halved the deficit on 75 minutes with a well directed header to set up a frantic finish.
Klasnic and Cahill came close to levelling in the latter stages as Wanderers threw everything at their opponents.
And although the equalising goal didn't arrive, Gary Megson could certainly be proud of the way his team performed in the second half.
With fixtures against CSKA Moscow and Liverpool to come for Manchester United over the next seven days, Sir Alex Ferguson made no less than eight changes to the team that drew with Sunderland a fortnight earlier.
Gary Megson, on the other hand, kept faith with the same eleven players that performed so admirably against Tottenham last time out.
As with the Spurs match there was another early goal, but this time it went the opposition's way rather than Bolton's.
Patrice Evra got free down the left touchline and chipped a cross into the penalty area which picked out Michael Owen. The striker nodded goalwards, and in an attempt to clear the danger, Zat Knight unfortunately sliced past Jussi Jaaskelainen.
There was nothing that the Finland international could have done to prevent the early goal, however he was perfectly poised to produce an early contender for save of the season in United's next attack.
Antonio Valencia reached the byline, lifted a cross into the area where Jonny Evans towered to plant a header goalwards. The home supporters in the East Stand were already on their feet in anticipation of a second goal, but Jaaskelainen threw himself to his right, palming the ball on to the post before gathering the rebound.
Berbatov volleyed wide from ten yards out in action packed first quarter of the match - a period which also saw Kevin Davies come very close to levelling the scores.
Sam Ricketts had advanced forward from right-back and delivered an exceptional cross with his weaker left foot. The Wanderers skipper had peeled away from both Rio Ferdinand and Evans, but couldn't direct his header on target.
Wanderers were in no way disheartened at conceding an early goal and created further opportunities to draw the scores level. Firstly a snap shot from Matt Taylor sailed over van der Sar's crossbar, before good wing play from Chung-Yong resulted in Davies misplacing a pass inside the penalty area.
Taylor twice caused panic for the defence with a free-kick and half-volley that tested van der Sar, but ten minutes before the break, Gary Megson's side were hit with the sucker punch.
A swift United counter-attack from left to right resulted in the home side's second goal of the afternoon on 34 minutes. The ball fell to Gary Neville inside the box and the former England defender cut the ball back to Valencia, who took a touch before firing past Jaaskelainen from 12 yards out.
Wanderers started the second half brightly and Knight tested the United goalkeeper with a towering header from a Taylor set-piece just four minutes after the restart.
But Bolton had to be wary of Manchester United's constant threat as Michael Owen twice came close to extending his side's lead. His scuffed shot was the better of the two chances after he had made a well-time dart from the right touchline.
Ivan Klasnic was introduced by Gary Megson as Wanderers changed to a 4-4-2 formation on 52 minutes.
Giggs twisted and turned inside the area to bring Jaaskelainen into the action, before the long-serving stopper made his second superb contribution of the afternoon when Berbatov shaped and connected with bicycle kick. But as with his save from Evans in the first half, Jaaskelainen spread himself fantastically to thwart the number nine's acrobatic effort
With the score at 2-0, Wanderers still felt that they were in the game going into the final 30 minutes.
Taylor saw a long-range attempt fly just over the bar, while Cohen was prevented from scoring his fourth league goal of the season by van der Sar.
The 1,500 travelling fans thought their team had halved the deficit on 71 minutes when Ivan Klasnic put the ball in an unguarded net, but referee Mark Clattenburg cancelled out his strike for an foul by Ricardo Gardner on van der Sar.
But there were to be no doubts when Taylor did reduce arrears just four minutes after the disallowed goal.
Having miscued his first cross, Kevin Davies did excellently to pick out the Wanderers wide-man with a delivery from the left touchline. Taylor out-jumped Evra and guided a well placed header past the helpless van der Sar.
The goal raised anxiety levels around Old Trafford, and with the wind under their sails, Gary Megson's pressed for the equalising goal.
The fightback was certainly on and Wanderers enjoyed a period of concerted pressure in and around the Manchester United penalty area. Knight had a shot deflected fractionally wide as the home side defended desperately to preserve their one-goal lead.
Sir Alex Ferguson made three substitutions to try and combat the series of Bolton attacks. Ivan Klasnic shot just wide from the edge of the box before the fourth official signalled four minutes of stoppage time.
And Zat Knight and Gary Cahill almost stunned the 74,000 nervous home supporters inside Old Trafford with headers in the added time. Cahill's was particularly unlucky because had he directed it a couple of yards either side of van der Sar, it would have certainly made the score 2-2.
The equaliser never came, but Wanderers could certainly be proud of their efforts in what was a typical gutsy display.
Man United: Van der Sar, Neville, Ferdinand, Evans, Evra (O'Shea 83), Valencia, Giggs, Owen (Welbeck 83), Berbatov, Anderson (Scholes 86), Carrick (Subs not used: Brown, Nani, Macheda, Kuszczak)
Bolton: Jaaskelainen, Samuel, Cahill, Knight, Ricketts, Muamba (Basham), Cohen (Mark Davies 63), Gardner, Taylor, Chung-Yong (Klasnic 52), Davies (Subs not used: Al Habsi, Robinson, Steinsson, McCann)