McCann currently has 28 players contracted for the 2023/24 campaign and wants to make at least one more addition to his squad before the transfer window closes on 1 September.
But he may need to start offloading those on the fringes to make way for new recruits.
The returning Rovers chief previously said he wanted a squad of around 23 players.
With that in mind, here’s a look at which players could leave Doncaster this summer.
5. Bobby Faulkner
Arguably the most promising prospect to graduate from Rovers' academy in recent years, Faulkner may get a chance at his hometown club depending on injuries and how well he does in pre-season. If not, a loan move is best to keep him playing regularly and developing. Photo: HOWARD ROE
6. Jack Degruchy
Degruchy impressed playing at right-back on loan with FC United of Manchester last term. With more senior options ahead of him in both that position and central midfield, his best bet may be to head out on loan again. Photo: Howard Roe/AHPIX LTD
7. Adam Long
Long struggled to make an impact on the starting XI following his move from Wigan last summer. With several senior options ahead of him - and Bobby Faulkner possibly ahead of him in the pecking order - it's hard to see a way in for him at present. Photo: Howard Roe/AHPIX LTD
8. Ben Bottomley
Bottomley has enjoyed several loan spells in non-league and with Louis Jones and Ian Lawlor in front of him more minutes elsewhere may be his best option. Photo: Steve Flynn/AHPIX LTD