Sussex Sharks are waiting on the fitness of Luke Wright for Saturday's FP Trophy quarter-final against Somerset Sabres.
The all-rounder is struggling with a toe injury and a late decision will made on his participation at Taunton.
Somerset are the form team in the competition having won all seven of their completed fixtures to romp through the group stage.
And Sussex, who have already lost wicketkeeper Matt Prior to England duty, face an even harder task if Wright is also sidelined.
"He is only 24," Sharks coach Mark Robinson said of Wright. "People forget that. And he's bowled really well for us this year.
"He has come back from England and done brilliantly for us, worked hard on his bowling and is building up some form going into the World Twenty20."
Although recent results suggest Somerset are strong favourites against a developing Sussex team, the omens are good for the visitors.
"It's a tough draw," admitted Robinson. "They are probably the form team in the competition but we have a very good one-day record at Taunton and I believe we have won our last six matches there."
Somerset's turnaround in one-day fortunes is down to a thorough winter analysis of their previous failings and a stack of runs from Marcus Trescothick.
Former England opener Trescothick is comfortably the competition's top scorer this season with a tally of 476, and has formed a dynamic opening partnership with wicketkeeper Craig Kieswetter.
"He is an incredible player who makes the game look so easy and that helps the person standing at the other end," said Kieswetter, who was born in South Africa but qualifies to represent England next February.
"Opening with him has relaxed me and allowed me to develop my game in terms of pacing an innings rather than just going gung ho early on.
"He can score 80 off 50 balls, which for our level is outstanding, and that helps set up games."
Saturday also sees two of the other three quarter-finals being played.
Essex Eagles, the holders, return to Old Trafford with the upper hand over group rivals Lancashire Lightning after securing a five-wicket win over the same opponents at the same venue on Wednesday, while Hampshire Hawks entertain Middlesex Panthers at the Rose Bowl.
The final last-eight clash - pitting Gloucestershire Gladiators against Nottinghamshire Outlaws - will take place on June 16 as Gloucestershire's Bristol ground is being used on Sunday for the second one-day international between England and West Indies.