The Premiership title race could come down to youth vs experience, with Celtic boasting one of the youngest squads in the division and Rangers the second oldest.
While captain Scott Brown might be one of the first players to come to mind when thinking about the Nine In A Row champions, their rest of their starting XI doesn't have the experience of the midfielder.
According to research from the CIES Football Observatory, Neil Lennon has fielded the the second-youngest average starting XI in the top flight so far this season.
Across their 10 matches so far Celtic's average age is just 26, with only Hamilton fielding a more youthful side.
On the other end of the scale Steven Gerrard's Rangers starting XI comes in at 27.8 years old, shy only of Kilmarnock at 28.5.
With the likes of Allan McGregor and Steven Davis mainstays at Ibrox that's perhaps no surprise, with 38-year-old Jermain Defoe also regularly involved.
On the European stage though Celtic have the edge in experience.
In their Europa League group Milan have the lowest average age of any team in Europe's top five leagues, with Lille coming in at 25.8.
Sparta Prague have an average age of 26 across their starting line-ups so far this season.
Their city rivals are up against Standard Liege with an average age of 25, as well as Lech Poznan (25.4) and Benfica (27.1).
Hamilton, with the lowest average age in the Premiership, have one of the youngest squads in Europe with only 13 sides from the top 20 UEFA nations fielding a younger average starting XI.
Scottish Premiership average starting XI age:
12) Hamilton - 24
11) Celtic - 26
10) Motherwell - 26.1
9) Dundee United - 26.3
8) St Mirren - 26.4
7) St Johnstone - 26.5
6) Ross County - 26.5
5) Livingston - 26.7
4) Hibs - 26.9
3) Aberdeen 27.5
2) Rangers - 27.8
1) Kilmarnock - 28.5
