Towers, the pre-season favourites to challenge Greater London Leopards for the league title, finished only sixth, lost the League Trophy final to Sheffield Sharks and were beaten in the National Cup semi-finals.
Their coach, Kevin Cadle, has won 17 titles in the last eight years, but now faces failing to win a single competition for only the second season out of 10. The Towers' record this season against third-placed Newcastle offers Cadle little encouragement for the three-game series.
The Eagles have lost only once in five games against the Towers and Cadle said: "We must be one up after tomorrow night, because trying to win twice at Newcastle could be well-nigh impossible."
The runners-up, the Birmingham Bullets, are away tonight to the Derby Storm. Mike Finger, the Bullets coach, said: "Ask any of the other coaches who they'd want to avoid in the quarter-finals and it would be Derby." Cadle might disagree, though.
Thames Valley Tigers, who finished fifth, open their series at home to Sheffield tonight and the champions, the Leopards, start at the Manchester Giants on Tuesday, when the other three ties enter the second phase.