Head coach Sadler not ruling out new signings to bolster Northants' survival bid
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The County currently only have one of their two allowed overseas signings in Australian Sam Whiteman, and he will play the final game of his stint against Lancashire on Sunday.
That means the the club will have room for two overseas players should they wish to sign any for the final three matches of the campaign against title-chasing trio Warwickshire, Surrey and Essex.
There is also the scope to bring in loan players from other clubs as rock-bottom Northants try to secure the wins they need to avoid relegation from the top flight.
"Discussions are ongoing," revealed Sadler.
"But it is obviously a bit of a budget thing and also an availability thing from other people as well around the country.
"We have had some issues with visas this year as well, and I have never known anything like it with overseas players.
"But discussions are going on, but we will have to wait and see. It will depend on budgets and availability."
Northants employed Australian seam bowlers Chris Tremain and Jordan Buckingham for three matches apiece in the first half of the red-ball campaign, and Indian batter Prithvi Shaw was also pencilled in for a mid-season stint, only for that to be thwarted by visa and passport issues.
Shaw eventually did arrive in time to play in the Metro Bank One Day Cup, before injury cut short his stint.
One player who will be available to play throughout September is Tom Taylor, who will be leaving the club at the end of the season to play for Worcestershire.
And Sadler says he intends to utilise the all-rounder in his final weeks at Northants.
"Tommy will give his all because he is a true pro," said Sadler. "He has expressed quite strongly that he wants to make sure he is available for these last four games, and at the minute he is still in our strongest side.
"And as long as we are still fighting to stay up we will pick our strongest team, and Tommy will certainly be in the mix for that as at the minute he is still a Steelback."
Northants go into the final four matches sitting rock-bottom of division one, and 25 points adrift of third-from-bottom Middlesex and safety.
They are 22 points behind second-from-bottom Kent, but do have a game in hand on the Canterbury-based side.
The Northants squad is due back for training at the County Ground on Tuesday as they build up towards that clash with Lancashire.