Brendan Rodgers already has his Celtic impact player - Ryan McGinlay

This is most common with backroom staff, as managers will regularly elect to work with people they know and trust from previous employment. Glen Driscoll, Celtic’s returning head of performance, has followed Brendan Rodgers to wherever the latter has managed for over 10 years. He joins up with fellow familiar faces in assistant manager John Kennedy and goalkeeping coach Stevie Woods, who Rodgers has also previously worked alongside.

Although most common in this particular form, the familiarity factor can also extend to players, as individuals sometimes make the move to wherever their manager of choice ends up. Defensive midfielder Nemanja Matic is a recent example of this, working with Jose Mourinho at Chelsea before following him to Manchester United and Roma, respectively.

In essence, these players will take less time to acclimatise to the manager’s methods compared to other individuals not yet used to what the new boss demands. By doing this, they are able to provide a clear example of what the manager expects from them, in turn taking the role of a messenger with regard to the manager’s tactics and instructions on the pitch.

Now in his second spell as manager of Celtic, Rodgers’ idea of an on-field familiar face may be a relatively small pool to operate in. A player who could undoubtedly make a telling impact such as Leicester City winger Harvey Barnes is way out of Celtic’s league in terms of price. Players previously operating in his Liverpool days will now be coming towards the peak or twilight of their careers, with most – if not all - of his Swansea City colleagues already retired.

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Swansea is where Rodgers reunited with Scott Sinclair, following the pair working together in Chelsea’s youth and reserve teams at the start of both of their respective careers as coach and player.

Sinclair was a big player for the Swans, scoring 24 goals in all competitions as his club finished third, before being promoted to the Premier League through the play-offs. Indeed, the winger scored a hat-trick at Wembley, as Swansea beat Reading 4-2 to secure Premier League football for the first time for both the club and Rodgers.

This fruitful reunion of the pair extended itself further in 2016, when Sinclair joined Celtic from Aston Villa. If ever there was a prime example of a familiar face coming in and setting the standard at a new club, then Sinclair must be high up on the list in terms of impact.

Just hours after signing his deal, Sinclair came off of the bench to score a late winner against Hearts at Tynecastle on the opening day of the league season. The ink on his contract was barely dry and the winger was already making a positive impact for Rodgers like he did previously, which turned out to be a success story for both player and club in the ensuing years.

This impact was felt for the duration of his time at the club, especially under Rodgers. In his first full season, Sinclair scored 25 goals in all competitions as Celtic completed an Invincible Treble, winning another two trebles in his time at the club. He left the club having scored 62 goals in 167 total appearances – not bad for a winger many quarters had written off following his move up north.

This success was recognised by both his peers and the press, winning both the PFA Scotland Players' Player of the Year and the SFWA Footballer of the Year at the conclusion of the 2016-17 Scottish Premiership campaign.

Sinclair operating on the wing for Celtic was like having an extension of Rodgers on the pitch for the team. The same could be said – although perhaps to a lesser extent - with regard to Kolo Toure, who joined Rodgers following his departure from Liverpool the season before.

The defender was also a familiar face for Rodgers, as the two worked at the Merseyside club together for a couple of years. Despite this, Toure would make less of an impact than Sinclair, only making 17 appearances in Rodgers’ first season before retiring in September the year after.

Although he played a minor role directly on the pitch, he would have been an invaluable member of the backroom team off of it, directly joining Kennedy and Woods as part of the coaching setup at Celtic following the conclusion of his playing career. He would later follow Rodgers to Leicester City before attempting to carve out his own managerial career at Wigan Athletic.

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With a shortage of names who could really make an impact as Sinclair did at the club, Rodgers may have to look in-house. A familiar player the 50-year-old keen to bring down south from Celtic following his 2019 departure was the club’s current captain Callum McGregor.

Following his return to the club last month, Rodgers made his failed transfer targeting of McGregor to Leicester public. He said: "I was keen to get him. Callum for me was someone who was perfect for the Premier League. He could come in and impose how I wanted to play and understand how I wanted to work and could play in different positions. He’s tactically brilliant, but I’m really glad he stayed now…I’m very happy he is the captain."

With a lack of previous impact players suitable for this role, perhaps McGregor will be the man to step up to the plate? 20 trophies already won at the age of 30, along with the captain's armband, would indicate that he is well up to the task of doing so if called upon by Rodgers.