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The summer transfer is due to open on June 15, and League One clubs are already getting deals done as Oxford United's rivals begin to strengthen.
The U's are yet to make a signing prior to the start of pre-season with some of their rivals already getting business done early.
Following their relegation from the Championship, United confirmed their retained list last month with 10 players departing and a further five returning to their respective parent clubs, including fan favourite Will Lankshear.
Oxford's expected rivals near the top end of the third tier next season have begun to make headlines with their early signings, including the likes of Plymouth Argyle, Stockport County, and Luton Town.
Stockport are the most recent side to bring in a new name.
County secured the signing of Ryan Glover on Monday from League Two side Barnet - the U's are set to face Barnet at The Hive in their second pre-season friendly next month.
The addition came two days after the club appointed ex-Rochdale boss Jimmy McNulty as their new boss, taking over from Dave Challinor after their 4-1 play-off final defeat to Bolton Wanderers.
Rochdale Manager Jimmy McNulty celebrates following victory in a penalty shootout after extra time in the Enterprise National League Final at Wembley Stadium (Image: Bradley Collyer/PA Wire)
Luton have also been swift in their dealings, apparently securing the addition of Bolton captain George Johnston on a free transfer.
The Hatters apparently beat off competition from rivals Stockport, Sheffield Wednesday, and Bradford City for the 27-year-old defender.
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Reporter Pete O'Rourke states that Johnston is due for a medical in Bedfordshire.
Elsewhere, Plymouth signed defender Alex Hartridge on a free transfer following the expiry of his contract at Burton Albion.
It was reported earlier that the Pilgrims were interested in bringing back loan star Alex Mitchell from Charlton Athletic on a permanent deal, with the U's also apparently interested.
Northern Ireland goalkeeper Conor Hazard (Image: Liam McBurney/PA Wire)
Also involving Plymouth is the transfer of goalkeeper Conor Hazard to Oxford's Thames Valley rivals Wycombe Wanderers.
The 28-year-old joined the Chairboys from Devon in Michael Duff's side's first signing of the summer.
Newly-promoted outfit MK Dons have also made strides in the market, as expected.
Stockport County's Adama Sidibeh and Stevenage's Charlie Goode battle for the ball (Image: David Davies/PA Wire)
The financially-strong Dons have signed defender Charlie Goode from last season's play-off semi-finalists Stevenage.
Goode won promotion to the Premier League with Brentford in 2021.
The 30-year-old joins on a free transfer having made 45 appearances for the Boro last term and will try and help Paul Warne's men make an instant impact on the third tier after finishing second in League Two last season.
Last week, Bradford signed Burton player of the season Jake Beesley and Wigan Athletic have re-signed Max Power from the Bantams.