The 2022-23 Celtic squad is being set up to withstand a potentially 60-game campaign competing across four fronts at home and abroad.
Just 10 matches into the season, Ange Postecoglou's depth of quality is set to face a considerable first test.
Up to eight Celtic players have been reported as carrying injuries, falling ill or otherwise of doubtful fitness in the past week or so.
Some will be at Postecoglou's disposal for the return of domestic football against Motherwell at Parkhead on Saturday while some will not.
So what's the state of play with these eight players as the international break comes to an end? Let's take a look...
Sead Haksabanovic
Summer signing Haksabanovic was subbed off after 32 minutes in Montenegro's match against Finland on Monday night after complaining of a left foot injury. The Montenegro assistant manager said afterwards that it "disrupted everything" but gave no hint as to the severity of his problem.
Alternatives if unavailable: Jota, James Forrest
David Turnbull
The midfielder was forced out of the Scotland squad with an ankle knock. Steve Clarke said it wouldn't have cleared up in time for the Dark Blues but did say Turnbull would be going back to Celtic "to get ready for their next game", suggesting it is minor enough that he could be in contention for Saturday.
Alternatives if unavailable: Reo Hatate, Aaron Mooy, Oliver Abildgaard, Yosuke Ideguchi
Giorgos Giakoumakis
Celtic's popular striker had a scan on a leg problem and reportedly trained alone but has been rated 50-50 to play against Northern Ireland on Tuesday night in quotes distributed in the Greek media. The match kicks off at 7.45pm BST with team news expected around an hour before that. It is worth noting that Greece have already topped their Nations League group and have virtually nothing to play for.
Alternatives if unavailable: Kyogo Furuhashi
Liel Abada
The 20-year-old was with the Israeli senior side initially but is to join up with the under-21s for their crucial Euros play-off final against Ireland on Tuesday alongside Eden Kartsev and Doron Leidner. Abada came off in the 2-1 win over Albania with what Israeli media called a muscle strain and subsequently underwent a test. The match kicks off at 6.15pm BST, with Abada making no mention of an injury problem in his post-game Instagram post.
Alternatives if unavailable: James Forrest, Jota
Daizen Maeda
After coming off at half-time in Japan's win over Greece, Maeda then pulled out of training with what the JFA called a right leg injury. Japan played Ecuador in Dusseldorf on Tuesday lunchtime with the 24-year-old missing from the squad altogether. His Celtic team-mate Kyogo Furuhashi started the game, with Reo Hatate making the bench.
Alternatives if unavailable: James Forrest, Jota
Cameron Carter-Vickers
The USA international setup called Carter-Vickers's injury "minor" but it was nonetheless still bad enough to force him out of the squad for St Mirren as well as the international break. Ange Postecoglou's only comment so far has been to say he hopes he is not out for too long, so there will likely be no official confirmation that he's able to return for Saturday until the manager's pre-match press duties on Friday.
Alternatives if unavailable: Stephen Welsh, Moritz Jenz
Carl Starfelt
Around September 10 or 11 it was suggested that Starfelt would be out for another month so that puts him until around the time of potentially the RB Leipzig home game (Tuesday October 11) unless the timescale has sped up during the international break. His is another one Postecoglou will be asked to provide an update on during his pre-Motherwell media duties.
Alternatives if unavailable: Moritz Jenz, Stephen Welsh
Greg Taylor
After a positive substitute appearance for the Scotland national side in place of the injured Kieran Tierney, hopes were high that the Celtic standout would start against Ukraine on Tuesday night. However, the Daily Record reports that the left-back is one of a handful of players affected by a virus meaning it's unlikely he plays against Ukraine on Tuesday. His availability for Saturday's match remains to be seen.
Alternatives if unavailable: Alexandro Bernabei, Josip Juranovic
This piece is an extract from today’s Celtic Digest newsletter, which is emailed out at 4pm every weekday with a round-up of the day's top stories and exclusive analysis from The Celtic Way team.
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