Newcastle have confirmed striker Leon Best is facing several weeks on the sidelines as he recovers from a knee ligament injury.
The 25-year-old Republic of Ireland international damaged his knee in a first-half block tackle with Stephen Warnock during Sunday's 2-1 Barclays Premier League victory over Aston Villa.
A club statement said: "Newcastle United can today confirm that Leon Best has sustained medial ligament damage to his left knee.
"The striker was forced off in the early stages of Sunday's home victory over Aston Villa having picked up an injury while trying to get a shot away.
"After being assessed by the club's medical staff, Best underwent a scan on Tuesday and will be out for a number of weeks."
Best was hurt in the 11th minute of the game and was replaced by debutant Papiss Cisse, who later announced his arrival on Tyneside with a stunning 71st-minute winner.
The former Coventry frontman has played a significant role in the Magpies' excellent season, making 19 starts and two appearances as a substitute, scoring four goals.
However, perhaps more importantly, he has for much of the campaign provided the support to leading scorer Demba Ba, who scored his 16th goal in 16 league games for the club at the weekend.
The consolation for manager Alan Pardew is that Cisse's arrival from Freiburg lessens the impact of Best's absence, and he has Shola Ameobi, Peter Lovenkrands and Hatem Ben Arfa as back-up to his Senegalese double-act.
Newcastle head into Saturday's tough trip to high-flying Tottenham in good spirits having climbed back into fifth place in the table as a result of Sunday's win, but knowing they will have their work cut out to return from White Hart Lane with something to show for their efforts with Best, Steven Taylor, Cheick Tiote and Yohan Cabaye all missing.