Celtic are reliant on the Hoops striker for goals but Beattie thinks the Bhoys cannot allow themselves to be short of cover in case the Parkhead prodigy is sidelined.
Rangers are reportedly keen on bringing Lawrence Shankland to Ibrox - but face competition from Celtic.
Ibrox side Rangers go to Parkhead to face Old Firm rivals Celtic in Sunday's Scottish Premiership derby.
Craig Beattie spent four years in Celtic's senior setup after being released by Ibrox side Glasgow Rangers.
Leigh Griffiths scored for Brendan Rodgers’s Celtic against Rosenborg in the Europa League last week.
Former Celtic striker Craig Beattie played with Scott Sinclair at Swansea City.
Brendan Rodgers’s Celtic have signed Odsonne Edouard on a permanent contract from Paris Saint-Germain.
Celtic have strolled to the Scottish Premiership title and have generally dominated the domestic game.
Celtic face Glasgow Rangers in the Scottish Cup semi-final this weekend, and Beattie has suggested that it could be a tough game.
Brendan Rodgers was confirmed as the new Celtic boss on Friday.
Jordan Henderson has been a star performer for Liverpool and England during these past 12 months.
Liverpool hero Divock Origi reportedly turned down a move to Premier League high-flyers Wolverhampton Wanderers in 2018 but will Nuno ever get his man?
Tottenham Hotspur are reportedly keen on Porto striker Ze Luis.
Jose Mourinho's Tottenham Hotspur have completed the loan signing of Gedson Fernandes.
Tottenham Hotspur are said to be interested in Wylan Cyprien, who has impressed for Nice this season.
Tottenham Hotspur defender Japhet Tanganga has been one of Jose Mourinho's side's stars over recent weeks.
West Ham United are still putting Darren Randolph through further tests, as they look to sign the Middlesbrough goalkeeper.
Leeds United appear to have an eye for a player.
Newcastle United are said to be looking abroad for players, after Steve Bruce met with Mike Ashley, but Everton ace Mason Holgate is a target.
West Ham United have been negotiating a deal for Middlesbrough's Darren Randolph, but there is caution around the London Stadium over the signing.