Celtic were particularly busy behind the scenes during the previous summer transfer window as they saw a lot of players move in and out of the club.

One figure the Hoops brought in during that period that has gone on to have a rather successful debut season at Parkhead is defender Carl Starfelt.

Signed on a four-year deal from Rubin Kazan for a fee of £4.5m back in July, the Sweden international went on to make 49 appearances for the Hoops across all competitions.

This shows just how quickly he became a crucial figure for Postecoglou in the team at the back.

To highlight his defensive output for the Bhoys, he ended the SPFL season with the second-highest number of interceptions (42) and tackles won (30) in the squad.

Now that the next summer transfer window has opened, this could give Postecoglou and the Celtic hierarchy to replicate a similar sort of masterclass they pulled off when signing Starfelt.

Earlier this month, it was reported that Celtic are one of the clubs eyeing a move for RKC Waalwijk defender Ahmed Touba.

After spending the majority of his career in Belgium, the 24-year-old joined the Dutch side back in August 2020 after leaving Club Brugge.

During his time with Waalwijk, the £900k-rated Algerian has made 62 appearances across all competitions, chipping in with three goals and two assists.

In terms of his defensive talent, he ended his latest domestic season in the Netherlands with the joint-highest number of interceptions (57) and highest number of tackles won at his club (32).

He also racked up the second-highest average of clearances per game (3.9) in the Eredivisie at Waalwijk. 

This highlights the similarities between him and Starfelt in terms of being a solid defensive unit for their teams.

Labelled as a "versatile" figure that "has all the assets to succeed" by journalist Chebli Ishaq on Twitter, Touba certainly has what it takes to be a solid addition to Celtic's ranks and continue their track record of signing players from abroad and turning them into important club figures such as Starfelt.

If the Hoops see an opportunity to secure a deal for the centre-back this summer, then they should do all they can to get him to Parkhead and strengthen Postecoglou's squad ahead of their new season.

In other news: "I was told..": Anthony Joseph drops Celtic transfer claim that'll worry Postecoglou