Former Coventry City, Hereford, Hednesford, Tamworth, Kettering, Ebbslfleet and Canvey Island midfielder Goodwin was appointed in mid-October as the successor to Wayne Thornhill.
The 37-year-old, who kicked off off his managerial career at Rothwell Corinthians before going on to guide Burton Park Wanderers, Irchester United and Long Buckby, left the Moatmen after securing a single win among four defeats in First Division South and a 2-0 exit from the Integro Doodson Cup at Buxton.
Along with skipper Jamie Barrett, Ricketts, pictured, had been working as Goodwin's assistant before his exit was announced a few hours after the club's league outing to Shaw Lane Aquaforce on Saturday was postponed.
The Moatmen confirmed the appointment of Ricketts and Barrett as his number two in a brief statement on their website thanking Goodwin for his services.
It read: "Gresley FC first team manager Scott Goodwin has been relived of his duties with immediate effect. Gary Ricketts has been appointed as player-manager assisted by Jamie Barrett. The club would like to thank Scott for his efforts in the last few weeks and wish him every success in the future."
Ricketts, 40, kicked off his career at Heanor Town before going on to score goals for Arnold, Hinckley, Hucknall, Nuneaton, Ilkeston, Salford and Mickleover Sports. He takes charge for the first time on Tuesday night when Gresley host Mickleover Sports in the third round of the Derbyshire Senior Cup.
Ironically, Thornhill stood down as manager after the club's 3-0 home defeat to Shaw Lane Aquaforce in September. That reverse followed a stuttering start to the club's First Division South campaign that had seen the Moatmen win three games away from home but fail to register a point at home.
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