Durham head coach James Franklin has called on his side to raise their game against the elite sides in the Vitality Blast to earn a spot in the knockout phase of the competition.

Franklin’s men have won three and lost three of their six games, although two of those defeats have come at the hands of the Lancashire Lightning – who are top of the North Group – including their five-wicket loss at Emirates Riverside last Friday.

Although Durham have produced impressive performances in their victories over the Leicestershire Foxes and the Northamptonshire Steelbacks, the New Zealander is hopeful that there is more to come from his team over the coming weeks to work their way to the quarter-final stage.

Franklin said: “We’re holding form at the moment. We’re winning one and losing one and that seems to be the way we’re going.

“It’s a little bit frustrating because I felt the Lancashire game was a good opportunity to put down a line in the sand against good opposition, particularly after our win against Leicestershire. Lancashire showed what a good team they were and they’re going to be there and thereabouts in terms of qualification. It was a good reality check for us.

“We’ve played well against Northants and Leicestershire. The likes of Lancashire, Nottinghamshire Outlaws and the Yorkshire Vikings, who are the perceived bigger teams in the competition, are the litmus test for us if we want to qualify and beat those teams.

“We’ve got a couple of big games coming up on the road against Northants and Derbyshire. We’re going to try to win at least one if not both of those games.”

The performances of D’Arcy Short have been a key factor in Durham’s three victories to date. Short arrived with a reputation forged in the Big Bash as the leading run scorer in the competition for the past two seasons.

The 28-year-old has lived up to the billing, scoring 245 runs in his six innings, including two half-centuries. However, Short has also been on form with the ball, utilising his left-arm leg-spin to great effect, leading the wicket column alongside Nathan Rimmington with eight strikes to his name.

“D’Arcy’s bowling has not been a surprise to us,” Franklin added. “It’s one of the reasons why we got him. We knew that he was a devastating batsman at the top of the innings, but we also knew that he could really contribute with the ball, particularly here at Durham.

“We knew that the uniqueness of his left-arm leg spin and it has proven to be the case. He’s not only scoring valuable runs, but he’s also taking valuable wickets. He’s proven to be a critical player for us.”

Durham are next in action in the Blast on Wednesday on the road against the Northants Steelbacks at The County Ground.