Chris Sutton believes Celtic may need to spend more than £50m overhauling their squad this summer if they are to retain their Premiership title and compete in the Champions League.
Martin O'Neill led Celtic to their fifth title in a row on the last day of the season in May as a fractured campaign on and off the pitch ultimately yielded a double, with victory over Dunfermline also securing Scottish Cup success.
However, whereas Celtic have enjoyed relative dominance in recent years, they were just minutes away from being pipped to the title by Hearts, with managerial turnover and off-field supporter protests over recruitment disrupting last season.
Sutton believes those recruitment issues are still a concern and thinks departures of key players could push Celtic into a bigger spend in the summer window as they look to address key areas in the squad.
"Martin worked wonders last season. I didn't see Celtic winning the title from the position which he was put in on a couple of occasions," he told Your Site News. "I mean, the run towards the end of the season was extraordinary but I still think you can't get away from the fact there needs to be a lot of change at Celtic in terms of recruitment.
"They've got the Champions League qualifier which is really important and, however exciting it was for Celtic fans to end up getting over the line last season, you can't get away from the fact that Celtic struggled at times throughout the season. So, Martin will be looking to, I'm sure, bring players in.
"It'll be interesting to see who goes out from Celtic. It looks like Reo Hatate will go, possibly Daizen Maeda, Arne Engels but they're big players for the team. So, who are Celtic going to replace those type of players with? I think that Celtic are possibly going to have to spend up to or more than £50m really because the squad does need a rebuild."
, live on Your Site, and will host Rangers in the first Old Firm clash of the season on September 20. Before that, however, they will have to negotiate a Champions League play-off tie on August 18/19.
Celtic failed to make the group stages of the Champions League last season, losing out in the play-offs on penalties to Kairat Almaty and Sutton thinks serious work needs to be done over the summer to ensure the club are back at Europe's top table.
"The squad looked tired last season at times," he said. "The question is, is the squad from last season good enough to win the Scottish Premiership this season, good enough to challenge in Europe? I think it would be a struggle again this season if Celtic don't bring players in. Everybody can see what needs to happen.
"I think Martin O'Neill will know that. So, recruitment is of paramount importance. And Champions League football, again, that Champions League qualifier is absolutely massive for Celtic. It can change the mood in and around the club. You get through that into the Champions League and the supporters will be delighted. You don't get through and then the old misery will start again."
in what will be Derek McInnes's first competitive match in charge.
Your Site pundit Kris Boyd says Rangers must start well after poor early season form helped to derail their title bid last time out.
"Going away to Dundee United is a good opening game, then Hibs at home and St Mirren after that, two home games, with a chance to build up some momentum before travelling to Aberdeen," Boyd said.
"For Rangers it is an opportunity to get points on the board. Rangers need to start the season well. Obviously, that didn't happen last season and they were playing catch up.
"They need to get off to a good start and see where that takes them because when you fall behind in this league it can be difficult to get back in and we have seen the amount of change that happened at Ibrox last season because of the poor start so I think for Rangers and Derek McInnes they will want to get off to a really good start."
and Sutton thinks Rangers will be better for the managerial change.
"Danny Röhl didn't have the stomach for it," Sutton said. "He walked away or, you know, he's gone to Salzburg. But Derek's stepping in.
"Last season at Hearts, they pushed Celtic all the way. I thought he did brilliantly. He's proven himself in management and I think it's a really smart appointment from Rangers, actually.
"When it came to the crunch at the end of the season, Rangers lost four games on the spin. Everything sort of changed then and Röhl's demeanour changed.
"And I don't think it was a great surprise to anybody that he ended up leaving. So, I think Rangers are better off without him. And, you know, Derek McInnes is a good appointment."
Hearts are yet to announce a replacement for McInnes and will have their own rebuild to contend with following the departure of captain Lawrence Shankland to Ibrox.
Despite that, Boyd believes Hearts are capable of challenging for the title again and insists Tony Bloom and Jamestown Analytics will be vital if that is to happen.
"Hearts have lost their manager and their captain and talisman in Lawrence Shankland but I think they will only get stronger," Boyd said. "Yes, last season they ran Celtic ever so close, but I think with Jamestown Analytics and a new manager they will get in shortly, then they will start to build again.
"It is brilliant for Scottish football because for a long time it has been Rangers and Celtic who were the only ones winning titles, with Celtic dominating recently. Now, all of a sudden, there is someone else in the mix and you are just hoping the likes of Hibs and Aberdeen, the bigger clubs, can come to the party as well because if they do then we've got a really exciting league."
Sutton has questioned if Hearts' best chance for title success was last season but knows Bloom will have a plan to have the team competing at the top end of the table again.
"This is going to be a very different Hearts side," Sutton said. "They are a really fascinating story because of what they achieved last season. Everybody will be thinking, well, can they challenge again? They've lost the best striker in Scotland, in Lawrence Shankland, to Rangers. They've lost their talented manager, Derek McInnes, to Rangers.
"What are Jamestown Analytics going to do in terms of trying to replace them? I'm sure they've got a plan. I'm sure Tony Bloom has a plan. It'll be interesting to see who comes in as the next Hearts coach and which route they go down.
"I'm sure Hearts will be there or thereabouts, but maybe it's the case that they had their chance last season. This season may be slightly different. I think that they're really interesting to watch."
