Defender Fiacre Kelleher (pictured) joins on a loan deal through to January from SkyBet League One Oxford United, while a trio of recent triallists have also committed for the 2017/18 season.
Forward William Mellors-Blair, striker Tristan Dunkley and defender Jordan Cullinane-Liburd all impressed enough during the Moors’ promising pre-season to earn deals for the forthcoming campaign.
Cork-born Kelleher, a 21-year-old centre-half, is an ex-Republic of Ireland under-19 international who came through the ranks at Scottish champions Glasgow Celtic.
After a loan spell at Peterhead, he joined Oxford on a two-year contract in June and appeared for the Moors in the pre-season victory over West Bromwich Albion on Tuesday.
Elsewhere, having spent time on the books of Manchester United and Walsall as a youngster, Mellors-Blair moved to America to study where he developed a prolific scoring record for National Premier Soccer League outfit Detroit City.
The 24-year-old returned to England last season and helped Evo-Stik South side Carlton Town to the Nottinghamshire Senior Cup.
Dunkley, a former Birmingham City trainee, makes the step up to the top tier of non-League football having shown plenty of promise further down the Pyramid with Worcester City and Evo-Stik Premier outfit Hednesford Town.
A former Loughborough University student, the 24-year-old spent the end of last season on loan at Halesowen Town after an injury-restricted spell with the Pitmen.
Meanwhile, like Dunkley, right-back Cullinane-Liburd is another talent familiar to McDonald from his previous managerial spells and will continue his progression in the National League having been a regular for Evo-Stik League South Premier side Redditch United.