WITH chairman Steve Gibson claiming Middlesbrough have been on an upward gradient under Steve McClaren's management, despite a recent blip, the climb gained more momentum at Deepdale.

Two shots brought two goals for the prolific Aiyegbeni Yakubu to secure Boro's passage into the sixth round of the FA Cup for the first time in four years.

The tie against Championship side Preston North End was far from easy, but Yakubu's potency in front of goal highlighted the difference between the teams, even if the African sensation initially struggled to come to terms with his marker's attention.

The multi-million pound striker converted the two opportunities that fell his way in the second half to ensure his reputation continued to rise.

Yakubu's first seven minutes after half-time was a stunning left foot strike that flew powerfully past former Boro goalkeeper Carlo Nash.

Nash, who managed only five appearances during his time on Teesside because of Mark Schwarzer's reputation, had nothing to do up to that point.

Yakubu completed the victory with a header at the back post, which Nash could only help into the net.

Boro, also on track for a place in the last 16 of the UEFA Cup for the second successive campaign, continue to put their earlier failings of 2006 behind them.

It is now four straight victories since the fall-out from the alarming 4-0 defeat at home to Aston Villa, when an angry fan threw his season ticket at McClaren.

But things are looking up for Boro, who know success in one of the cups is paramount this season after struggling at the wrong end of the Premiership table.

McClaren kept things ticking along nicely by scrapping the lone striker approach that had been so effective in memorable triumphs over Chelsea and Stuttgart. He started with those tactics in Lancashire but had to have a rethink at half-time after a poor opening 45 minutes.

There was the usual tinkering to the personnel, highlighted by Tony McMahon becoming the 32nd player to have played for Boro in all competitions this season after returning from a long-standing shoulder problem.

There was also good news on the injury front for Franck Queudrue, who made his first appearance of the year after being sidelined with a knee problem. That meant captain Gareth Southgate started on the bench.

But where the decision to rest the skipper will have been accepted, it is unlikely Jimmy-Floyd Hasselbaink will have been pleased to hear his reward for scoring in Germany was to make way for Yakubu.

McClaren - aware Hasselbaink has netted five in his last seven games - will point to the fact that, with so many matches, rotating his squad is essential if he is to get the best out of his men. But the start made by Boro did not suggest it had worked.

Preston, in the Championship play-off mix having gone 25 games unbeaten since the back end of September, have been playing with plenty of confidence and that was reflected in the opening exchanges.

Striker David Nugent had a long-range effort deflected just wide of Schwarzer's left post and the striker then struck a low shot into the arms of the Boro No 1.

Preston's tactics - to switch from a five-man defence to a three- man attack when in possession - caused Boro all manner of problems for most of the opening period, particularly in midfield.

Such was the way the opening half developed, Preston's huge share of the play resulted in Boro panicking when they did get the ball. Instead of taking their time and picking a pass, all too often a hoof upfield proved ineffective.

A major contributor to that was Yakubu, the only Boro man near the half-way line. He was initially bossed by the Preston central defensive pairing of Youl Mawene and Claude Davis, making a mockery of the way he tortured established internationals John Terry and Ricardo Carvalho in Boro's recent crushing of Chelsea.

On the one occasion Boro and Yakubu did manage to force their way into the Preston box the Nigerian was lucky to escape a booking when he crashed to the floor, looking for a penalty under a challenge from Mawene.

There were no theatrics involved moments later, though, when teenager Lee Cattermole was introduced in midfield after Fabio Rochemback had to be stretchered off following a late foul from Davidson.

From the resultant free-kick, Pogatetz's attempted header bobbled towards Nash, who was able to use his hands for the first time in the half - not ideal for Boro when you consider it was on the stroke of half-time.

There was another change made by McClaren at the interval as he attempted to stop the constant flow of Preston attacks by introducing a second striker to help share the work-rate being heaped on the shoulders of Yakubu.

And Hasselbaink, professional in the past when asked to come on and responsible for scoring the two goals against Coventry in the previous round, was quick to get involved again, albeit in the referee's ear for not awarding a free-kick for a foul on Mendieta.

The Dutchman has been renowned for his tantrums over the years but he has also built up a reputation for delivering on the field of play and he didn't disappoint within seven minutes of his introduction.

Hasselbaink's flick from Queudrue's throw-in on the halfway line fell into the path of Yakubu. The £7.5m man outmuscled his marker before placing a dipping volley beyond Nash's outstretched left hand.

Conceding the goal was harsh on Preston but proved to be Boro's reward for a staunch defensive display in which the home side were restricted, largely, to long-range drives.

The powerful figure of former Wimbledon striker Agyemang had two shots that failed to seriously test Schwarzer, while Nugent also fired one narrowly over the bar from 25 yards.

When the Aussie keeper did have to prove his worth he obliged with a fine save to deny a close-range header from Mawene when he rose to meet Paul McKenna's free-kick.

McKenna then went close himself with another set-piece but his left-foot curler from 22 yards dropped just inches wide and Boro's lead was preserved.

Preston's failure to turn possession into goals proved to be their downfall.

Yakubu showed them exactly what they lacked by paying back another piece of his transfer fee 13 minutes from time.

Downing's free-kick from the left evaded everyone and fell kindly for the former Portsmouth front-man at the far post and his diving header could only be helped into his own net by Nash.

Yakubu was withdrawn and replaced by Southgate as Boro kept their goal intact and secured progress into the quarter-finals of the FA Cup for only the second time in nine years.

Result: Preston North End 0 Middlesbrough 2.

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