Colin Munro believes fellow New Zealander Mitchell McClenaghan will bring the "X factor" to the Worcestershire attack as the overseas replacement for Saeed Ajmal.
Paceman McClenaghan is poised to make his debut in Friday's NatWest T20 Blast clash with Northamptonshire Steelbacks at Northampton.
He is then set to make his first LV = County Championship appearance against Gloucestershire at Cheltenham starting on Monday.
Munro said: "The bowling unit has done a wonderful job this year. The pace guys, young Charlie Morris and Jack Shantry, do a great job at holding up an end and going at only two an over and it has allowed Saeed to do what he does.
"Mitch will bring a lot of energy, a guy who wears his heart on his sleeve and plays every game to the fullest.
"He will bring a bit of aggression and a lot of pace to our attack in the four-dayers, one-dayers and even the back end of the Twenty20.
"With Mitchell running in with the duke ball, which swings a bit longer than the kookaboro ball, I think he will be really good for the club moving forward.
"He has got that X factor and that attitude of he never wants to lose, plays really hard and wears his heart on his sleeve and you know you are going to get 100% whatever he is doing.
"I played club cricket with him and he still runs in and tries to bowl at 150 kms. He is never going to do anything half heartedly. He is always going to put in 100%."
McClenaghan made a big impact in last summer's ICC Trophy in England with 11 wickets in three games, including three against England, before enjoying a successful spell of T20 cricket with Lancashire.
Munro said: "He was really close to getting the record for the quickest one-day 50 wickets.
"I know he was a bit gutted to miss out on that. He has had a fantastic start and hopefully it can continue for him.
"He has worked really hard coming back from his injuries and stuff so he deserves everything that comes his way."
