The Pools boss completed the signing of experienced goalkeeper Kyle Letheren last week after his exit from Morecambe with the 34-year-old joining as a player-coach to complement the backroom staff as well as provide competition in goal for current No.1 Ben Killip.
Hartley and Letheren go back to their time together at Dundee in 2014 where Hartley spent three years in charge at Dens Park.
The Pools boss spent a decade in management north of the border across four teams earning five promotions along the way.
But following the signing of a former player in Letheren, and links to another ex-player in defender Reghan Tumilty, here at The Mail we look at some of Hartley’s former players from the teams he has managed and who he could look to reunite with at the Suit Direct Stadium.
1. Mitch Megginson
Megginson was a key component in Hartley's title winning Cove Rangers side last season scoring 24 goals. Megginson started out with Aberdeen and also played under Hartley at Alloa Athletic (Photo by Jeff Holmes/Getty Images)
Photo: Jeff Holmes
2. Greg Stewart
Stewart is another striker who enjoyed some success under Hartley at Dundee before moves to Birmingham City, Aberdeen and Rangers transpired. The 32-year-old has recently agreed to join Mumbai City but could be one Hartley may monitor. (Photo by Ian MacNicol/Getty Images)
Photo: Ian MacNicol
3. Kane Hemmings
Hemmings moved to Tranmere Rovers in January and scored eight times in the second half of the campaign. Hemmings played under Hartley at Dundee in 2015/16 scoring 21 times. (Photo by Pete Norton/Getty Images)
Photo: Pete Norton
4. Kevin Holt
The fullback made over 100 appearances for Dundee after being brought in by Hartley in 2015. Holt, 29, currently plays for Partick Thistle having joined last summer. (Photo by Mark Runnacles/Getty Images)
Photo: Mark Runnacles