Lancashire have signed wicketkeeper Phil Mustard on loan from Durham after Alex Davies suffered a knee injury.
Ex-England one-day keeper Mustard, 32, has scored just 51 runs in seven first-class innings for Durham this season.
Davies, 21, made 730 runs at an average of 40.55 as Lancashire secured promotion from Division Two.
"Alex has played tremendously well for us this season and to lose him at this stage is a blow," Lancashire head coach Ashley Giles said.
"But Phil has a tremendous pedigree and will slot into the squad seamlessly for two crucial games as we hope to finish the season with another trophy."
Lancashire are vying with Surrey for the Division Two title and they meet in their next game at Old Trafford, starting on 14 September.