With the summer transfer window shutting on September 2, Sky Sports News reporter Charles Paterson examines the potential activity that could yet happen across the Scottish Premiership.
Who could Celtic sign?
Neil Lennon is confident that Celtic will do business between now and next Monday and he is on the record saying that he would like two new full-backs, one on either side.
The Celtic boss even went as far as suggesting any incomings could travel to Sweden with Celtic for Thursday's Europa League second leg, despite being cup-tied, so they could help embed themselves ahead of a potential debut in Sunday's Old Firm game.
Two prime candidates stand out at left-back: Greg Taylor of Kilmarnock and Birgir Meling of Rosenborg.
Celtic have made an enquiry for Taylor, but are yet to make a formal offer, and they have reportedly been quoted £3m as an asking price.
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Sources close to this deal have suggested Killie's valuation is unrealistic; Bundesliga side Nuremburg were told during the summer that Taylor could be bought for £1m, but again no offer was ever made.
Celtic have walked away from moves involving other Scottish clubs before when they have felt the asking price has been too high; last year's saga involving John McGinn immediately springs to mind.
Taylor is a Scotland international and one of the most promising young players in the country, his stock rose last season under Steve Clarke.
Now he is in a Kilmarnock team that is bottom of the league and, theoretically, in dire need of reinforcements.
Cashing in might make sense to Killie's long-term plans, but the price must be right for both parties.
Meling has been tracked by Celtic for some time and fits the profile of what the Scottish champions are looking for as a replacement for Kieran Tierney.
At 24, the Norwegian international has experience, but also possesses sell-on value; whether he would be better value than Taylor is arguable.
Celtic also require a right-back as competition for Hatem Abd-Elhamed, and there might be room for another centre-half, though Nir Bitton has performed admirably there when required.
A new striker is a possibility, but given the way Lennon shapes his team, it is hard to see how he would keep four strikers happy.
In terms of departures, Lennon has stressed he is keen to trim the fringe players. Scott Sinclair appears to be on the fringes, but there may be nowhere for him to go.
Craig Gordon's game-time could be severely limited now Fraser Forster has arrived, while Jonny Hayes and Tony Ralston could also be given a route out.
The pundit's view - Kris Boyd
"At left-back, Greg Taylor has proven over the last number of years that he has been a success in Scotland.
"Are Celtic going to be a success in Europe? No. Therefore you look and see what the best talent is to get you over the line in Scotland.
"This could be the only opportunity Taylor has of moving to a big club like Celtic.
"I can understand why Taylor's representatives trying to push his exit through because it is a life-changing move and one where Celtic would be getting a top player.
"With Craig Gordon, he has had to sit on the sidelines when Scott Bain was playing so I do not think Craig would be happy with that.
"The move to Chelsea was stopped because Celtic wanted him to stay at Parkhead a few years ago.
"I do not think he will be very happy now, I know time moves on but now that Forster is in, he finds himself as effectively the third-choice keeper."
What could happen at Rangers?
The prime concern at Ibrox this week is ensuring that Rangers' two most valuable assets remain at the club.
Interest has swirled around captain James Tavernier and striker Alfredo Morelos for over a year, yet they remain the key cogs in Steven Gerrard's side.
To lose either of them now would cause huge upheaval.
Gerrard clearly stated at the start of the summer that he did not want to encounter a scenario where Morelos departed with no time to be replaced.
Rangers have dealt with speculation around the Colombian for 18 months, yet no firm offer has ever materialised.
The Ibrox club are understood to value Morelos at the same price Celtic sold Moussa Dembele to Lyon for, around £20m.
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If a proper bid even close to that number was to emerge, considering what Gerrard has said on the issue - notwithstanding the deafening silence from Morelos himself - one gets the sense that Rangers would take the money.
The manager has grown weary of being questioned about Morelos and challenged the striker - partially tongue in cheek - to clarify his intentions a few weeks ago.
On form and in the mood, Morelos is the catalyst that can fire Rangers' title bid, yet nobody knows if he really fancies that challenge.
Interest in Tavernier has largely been confined to the Premier League and Championship, but with both league's deadlines now passed, it seems the right-back will stay put for now.
It is left-back where Rangers have struggled to find fluency, with Jon Flanagan solid if unspectacular and Borna Barisic looking unimpressive - until his wonder-goal against St Mirren on Sunday.
Could that be the spark he requires to make the position his own?
Two big performances this week against Legia Warsaw and Celtic are required to back up that theory.
With a return for Ryan Kent looking unlikely - though not impossible - Gerrard appears happy with the rest of his squad, but he admitted on Sunday he might be powerless if his board receive offers for players this week.
Forward planning has been Rangers' strong suit this summer, but the manager will hope there is a back-up plan available if circumstances conspire against him between now and Monday.
The pundit's view - Kris Boyd
"If there are concrete bids between now and the end of the transfer window for Morelos then I am sure Rangers will have something up their sleeve because, if they want to challenge Celtic and in the Europa League then they cannot go into the season with Jermaine Defoe as their only recognised striker.
"At left-back, yes Barisic scored at the weekend but we have seen Andy Hailliday and Jon Flanagan in that position too.
"I can see why Gerrard goes to Flanagan in the big games; when Tavernier bombs down the right then Flanagan tucks in to make a back three and that helps Rangers.
"The natural instincts of Barisic and Flanagan are to get forward.
"If you take into consideration the Europa League qualifiers and the Old Firm this week there is still time to get business done.
"If either Rangers or Celtic fail to get through to the Europa League, then both teams will be trying to shift players."
Elsewhere in the top flight
Most Scottish Premiership clubs did much of their business early in the summer, but some are still on the lookout for personnel as the deadline approaches.
As mentioned above, plans at Kilmarnock may hinge around Greg Taylor's future; if the left-back leaves then cash could be reinvested elsewhere.
Niko Hamalainen is a like-for-like replacement for Taylor, but it's further forward where they need help - Eamonn Brophy has cut a forlorn figure at times and requires support.
Derek McInnes has hinted his Aberdeen squad is complete, but the injury to Scott McKenna at the weekend could mean he seeks centre-half cover.
One man who might finally leave Pittodrie is striker Stevie May - a move to St Johnstone has been on and off all summer but could finally get the go-ahead this week.
May's return would be a welcome boost to Tommy Wright who is struggling for numbers, as new contracts to Zander Clark and Jason Kerr have eaten into his budget.
Experienced defender Richard Foster could leave McDiarmid Park before the deadline after a reported bust-up with the manager.
Hearts sit second-bottom of the table and are without a league win since March, but are expected to bring in Ryotaro Meshino on loan this week to add creative flair.
The Japanese attacker is seen as a future star by Manchester City who have loaned him out immediately after signing him.
Across the city, Hibernian have made several major signings through the summer, but may be vulnerable to offers for striker Florian Kamberi, who has reportedly been scouted by Basel.
Paul Heckingbottom will want to keep the Swiss striker who already has five goals in all competitions this season.
St Mirren manager Jim Goodwin is still searching for one or two additions, but his biggest success may be hanging onto Vaclav Hladky - a bid from Qarabag for the Czech goalkeeper was rejected earlier summer.
When does the transfer window close?
Thought the transfer window was closed? Wrong. Across Europe, plenty of deals are still being done, with Premier League players still able to move to the continent.
The transfer window for Spain's La Liga, Italy's Serie A, Germany's Bundesliga and France's Ligue 1 closes at varying times on Monday September 2. Meanwhile, League One, League Two and Scottish clubs' can also do deals until September 2.
Follow our Transfer Centre blog for all the latest news and rumours from the window...