Aberdeen – Jonny Hayes
Christian Ramirez and Marley Watkins have been mere squad players, while Connor McLennan is on loan at St Johnstone. Hayes, however, is still a key player at Pittodrie. The Irishman will be 36 by the start of next season and has missed a chunk of this campaign with a groin injury. JIm Goodwin has praised the player’s professionalism and fitness and has started the winger when he’s been fit.
Celtic – Conor Hazard
It's credit to Celtic that they have all their key players under contract next season. Goalkeeper Hazard, however, returns from HJK Helsinki having helped the Finnish giants win the Veikkausliiga and qualify for the Europa League group stages.
Dundee United – Charlie Mulgrew
The former Celtic, Aberdeen and Blackburn Rovers star was this weekend announced as a player-coach, working as part of Liam Fox’s backroom staff while still being available for first-team duties. What does the medium-to-long term hold? The 36-year-old was brilliant last season but, like many of his team-mates, hasn’t hit the same heights. It will be interesting to see if he hangs up his boots to concentrate on his coaching career.
Hearts – Liam Boyce
Two seasons ago the Northern Irishman was both the club's best No.9 and No.10. Now he is second in both areas behind Lawrence Shankland and Barrie McKay. When he tore his cruciate ligament in August there were fears he may have played his last game for the club. Yet, the extent of his influence has been witnessed in his absence. An extension would be likely.
Hibs – Josh O’Connor
Yes, Ryan Porteous is in the same boat but it would be a huge surprise if he extended his stay at Easter Road with a number of Championship clubs reportedly interested. O’Connor is a very interesting one, however. The son of Hibs legend Gary, the 18-year-old featured once last season but has not been part of Lee Johnson's plans despite the team's struggles in forward areas. If he was not to be kept on he wouldn't be short of offers.
Kilmarnock – Alan Power
No team have more players out of contract than Killie with 20. After his performances in the first half of the campaign, securing winger Dan Armstrong on a new deal was a key move. Club captain Alan Power has also been an important figure in the middle of the park, starting all 16 Premiership matches this season, but he turns 35 in January and his Rugby Park future remains uncertain.
Livingston – Jack Fitzwater
There are plenty of players’ contracts Livingston will likely want to extend, including Jason Holt, Ayo Obileye and Cristian Montano, while they have a year option for Joel Nouble. Fitzwater was excellent last season, much more consistent than his first at the club and even led to him being linked to the English Premier League. This campaign, after being out of the team for a spell, he has helped Livi to the best defensive record outside the Old Firm.
Motherwell – Stephen O'Donnell
The likelihood of the Scotland international extending his stay at Fir Park is certainly up for discussion. It is only recently that he has been back in the team following an injury to Paul McGinn who is also out of contract at the end of the season. O’Donnell’s consistency hasn't been near that which led to him earning 26 caps for his country. It is fascinating to see where he could end up if he left.
Rangers – Steven Davis
The veteran midfielder will go through the same routine he has the past couple of seasons with questions over his future at Ibrox and whether this will be his last year. Yet, the Northern Irishman continues to show his worth on the pitch. His composure and range of passing can't be replicated by any of his team-mates. He is soon to be 38 but if his performances continue at such a level, why wouldn't you keep him?
Ross County – Alex Iacovitti
The no nonsense centre-back has been an excellent signing for Ross County and served them so well these past few seasons. So much so that you would expect there to be interest in the 25-year-old who has improved with experience and game time, no one at County has played more minutes in the last three campaigns. He is left-footed, decent on the ball and strong in the air.
St Johnstone – Eetu Vertainen
Let's face it, Stevie May, Chris Kane and David Wotherspoon will likely be Saints players next season. It’s hard to say the same for Vertainen. Having arrived with expectation he has spent a chunk of the last two seasons in Northern Ireland with Linfield where he has performed well. Will it be enough to earn another shot under Callum Davidson?
St Mirren – Ethan Erhahon
The 21-year-old is an excellent player. Agile, energetic, combative and composed on the ball. He has been a key player for the Buddies this campaign but perhaps just lacks that wee bit of consistency which will take him to the next level. He is a talent who would be a fine pick-up by clubs north and south of the border and one which can be developed even further.