KEVIN KEEGAN acclaimed his greatest legacy to Newcastle, then posed the question no Geordie dares contemplate.

Who replaces Alan Shearer when he retires at the end of next season?

As the Magpies' messianic manager it was Keegan, of course, who lured Shearer back to his native Tyneside from Blackburn Rovers in a then-world record £15m deal.

Over seven years have since elapsed, and 33-year-old Shearer is still breaking records and passing milestones.

On Saturday, he clocked up his 450th career League start and marked the occasion with a double strike which brought up a personal century of goals under the St. James' Park stewardship of Sir Bobby Robson. Shearer now has 12 to his name this season and is the Premiership's top marksman with 11.

England coach Sven-Goran Eriksson was there to witness the return from injury of Jonathan Woodgate and Kieron Dyer, as well as assess the form of emerging star Jermaine Jenas.

But, watching former England captain Shearer express his art, Eriksson must have wondered what might have been had this striker par excellence not felt constrained to hang up his international boots after Euro 2000.

The gnawing pain of tendinitis in a knee persuaded Shearer that something had to give and Keegan, his last England manager, is certain his old charge will time it right again when he finally calls it a day altogether.

Keegan, you suspect, believes England - let alone Newcastle - may never see his like again.

"Alan is a master of his trade,'' said the Manchester City boss. "I don't think there is anyone better than him in the world at what he does.

"People thought £15m was a lot of money when I brought him here, but I thought then it was a great signing and, as every year goes by, he proves more and more that he was good value.

"I don't know how they will replace him, but they'll have to do that one day. If he could play against us every week, he'd probably play for another 20 years!

"Seriously, though, he's so clever; he doesn't try to do things he can't do.

"He gets free-kicks when sometimes he's committed the foul - and I don't mean that disrespectfully - and he scores goals.

"He's a leader and there aren't many in football now - he's a throwback. He'll want to finish while he's still pretty much at the top. Getting that right is tough, but he got it right with England.

"It's hard to believe that a few years ago (under Ruud Gullit) he might have been going out of here; there were even rumours he might have been going out in the close season.

"As you get older, you need younger players to bounce off and keep you going; I had to do that as a player when I came here, and Peter Beardsley did that for me.''

Shearer, perhaps, has a similar scenario in the making with Craig Bellamy, but the Welshman's own tendinitis problems have interrupted the flow.

Consequently, Shearer is precious to Newcastle and, with one eye on Thursday's UEFA Cup visit of Basel, Robson admitted he considered taking his "talisman'' off late on against City, but kept him on in the hope he would complete a hat-trick.

By then, Newcastle had a vice-like grip on the game, but their dominance was slow in coming.

It wasn't until late in the first half that they began to take control, Shearer carving out Laurent Robert a great chance which Sun Jihai contrived to block, before the winger served up a teasing cross that somehow eluded Dyer inside the six-yard box.

But another wicked delivery from Robert in the 56th minute gave Shola Ameobi, making his 50th Newcastle start, the opportunity to force home past David Seaman after Steve McManaman had got in the way of the England Under-21 international's initial header.

Shearer's outstretched leg almost reached Ameobi's cross before Olivier Bernard conjured the sort of ball his skipper thrives on.

The left-back kept the ball in play in miraculous fashion before gaining a yard on Sun to whip over a stunning centre which Shearer headed home with venom.

Seaman, whose ludicrous ponytail had been loosened in a crunching first-half collision with Shearer, survived another hairy moment when he was forced to perform a double save from Ameobi and Jenas ten minutes from time.

But five minutes later, Shearer settled the issue. Bernard centred again, Ameobi provided the knockdown and Shearer bundled the ball in at the second attempt to defy Seaman.

This win lifted Newcastle to sixth place and Robson was lavish in his praise for his entire team. He said: "We regret the bad start we had to the season, but we can't change it. You never know the dip Chelsea might have, or what might happen to Manchester United in the new year.''

The left-sided link-up between French pair Robert and Bernard is offering an increasingly productive supply line.

After frustrating his manager for so long, Robert is flavour of the month; proof of that was the standing ovation he received when substituted near the end of his 100th Newcastle appearance.

Robson said: "Robert is benefitting from being here two seasons and acclimatising to English football. He knows the need to work hard now, his effort up and down the line was good. He's tired at the end of games now - he wants to be off - and that's indicative of the extra work he is putting in. Before, he came off without his shirt being dirty.

"I thought Bernard was excellent in the second half. He was strong, covered well and kept Trevor Sinclair, who's a good player, under lock and key.''

Now, Newcastle must find the means to break in to the top four if they are to rekindle their Champions League dreams.

Result: Newcastle United 3 Manchester City 0.

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