NEWCASTLE have been rocked by the news that midfielder Jermaine Jenas faces up to a month on the sidelines.

A scan today is expected to reveal the former Nottingham Forest man, who turned 20 last Tuesday on the day his manager became a septuagenarian, tore ankle ligaments in training on Friday.

The news couldn't come at a worse time for the club, or the £5m signing, with the Magpies challenging for Premiership and Champions League honours and Jenas having just forced his way into the England set-up.

An exasperated Sir Bobby Robson said: "It appeared to be a nothing sort of incident.

"He went to shoot and felt a little tear and a sharp pain. He couldn't quite walk sensibly and then it died down. We packed it in ice and he appeared alright later on. We gave him a test (on Saturday morning) and he was nowhere near playing."

Robson's worst fears could be realised this morning with a scan likely to reveal the full extent of the injury on a player he now rates in the £10m bracket.

"If the scan's a tear and then your talking about two, three of four weeks," he said.

"It's bad for us and for him - he's doubled his value."

Jenas has been in the form of his life since Christmas finally ending his Magpies drought in front of goal with a run of four goals in five games.

His form saw him called into the international set-up and he impressed on his England debut against Australia at Upton Park earlier this month.

His second-half showing was such that the England management team are considering him as a possible solution to the national side's left-sided problem.

Sven-Goran Eriksson's assistant Tord Grip watched him in Leverkusen, and the injury will be a blow to any immediate plans they had for the youngster.

The injury is likely to rule him out of the Euro 2004 qualifiers away in Liechtenstein at the end of March, and at home to Turkey at the Stadium of Light at the beginning of April.

The news for Newcastle was however tempered by the imminent return of Portugal international Hugo Viana. The 20-year-old has completed his recovery from a dislocated shoulder and is expected to be back for Wednesday's Champions League game at home to Leverkusen.

* Newcastle United have offered 22-year-old Scotland international Steve Caldwell a new deal which will keep him at St James' Park until the end of next season. The defender is out of contract this summer and talks are on-going with his representatives.

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