The Magpies midfielder admits he "can't really answer" why his side were so lacklustre in their vital clash at Villa Park.
Newcastle United midfielder Jack Colback has admitted to BBC Newcastle that he cannot understand why his side were so poor in their 0-0 draw with already-relegated Aston Villa in a vital penultimate fixture of the season on Saturday.
The Magpies came into the clash at Villa Park on a roll having won two and drawn two of their previous four matches, and were being tipped by most to take a giant leap towards survival with victory over the hapless bottom club.
Instead, Rafael Benitez's side toiled to a flat goalless draw which leaves their hopes of survival hanging by a thread after Sunderland's dramatic 3-2 victory over Chelsea.
Colback bemoaned the lack of momentum during the game, which was disrupted on several occasions by the Villa fans, who in a fine display of gallows humour were throwing a beach-ball-laden party on the Holte End for the last game of their unbroken Premier League era.
However, the 26-year-old midfielder did admit that his side lack ruthlessness and the energy of recent weeks as they potentially fatally failed to secure all three points.
Colback told BBC Newcastle: "We never really looked under threat defensively, but we never really had that killer instinct going forward. I can't really answer the question as to why - we knew how big the game was. It's difficult to put your finger on it.
"I don't know whether a bit of fatigue kicked in or what, but we weren't quite as energetic as we have been. Obviously the beach balls and inflatables getting put on the pitch made it difficult. We didn't really get momentum in the game. It was stop-start."
Newcastle host Tottenham Hotspur at St. James' Park on the final day of the season on Sunday, but their fate could already be sealed by the time that match kicks off if Sunderland can beat Everton at the Stadium of Light on Wednesday.