Sir Rod Stewart, 79, spends some quality time with his son Alastair ...

Sir Rod Stewart spent some quality time with his son Alastair on Saturday as they watched his beloved team Celtic FC secure a win over their fierce rivals Rangers at Celtic Park in Glasgow. 

The music legend, 79, appeared to be in high spirits as he watched, from the stands, Celtic go up against Rangers in a thrilling Old Firm Derby. 

It was a tense game with Celtic securing the win finishing 2-1 after the team scored two goals in three minutes in the first half, one being an own goal. 

Rod was suited and booted for the special occasion in one of his signature suits as he watched his club go head-to-head with Rangers for a chance of winning another Scottish Premiership title. 

He was also joined by rarely-seen son Alastair, 18, who was spotted in the stands intensely watching the game with his father. 

Sir Rod Stewart spent some quality time with his son Alastair on Saturday as they watched his beloved team Celtic FC secure a win over their fierce rivals Rangers at Celtic Park in Glasgow

The music legend, 79, appeared to be in high spirits as he watched from the stands his beloved Celtic go up against Rangers in a thrilling Old Firm Derby

Rod appeared a little dishevelled as he watched the game unfold with his shirt undone and his tie loose. 

In another snap, the rock legend appeared in very high spirits as he celebrated the big win.

During the game, Celtic ultimately prevailed to go six points clear of their fierce rivals with only two games left to play this season. 

It comes after Rod beamed as he and lookalike son Aidan watched beloved team Celtic FC smash Hearts 3-0 in the Scottish Cup at Celtic Park in Glasgow earlier this month. 

The iconic musician was suited and booted and spotted in the stands with the smartly dressed 12-year-old, whom he shares alongside son Alistair with wife Penny Lancaster, 53. 

Sir Rod wore his blonde locks in his signature spiked style and couldn't wipe the smile off his face by the end of the game.

He also posed for snaps with fans and fellow Celtic supporters while he celebrated the team's historic win. 

Aiden joins Rod's vast brood Sean, 43, and Kimberly, 44, with ex-wife Alana Stewart; daughter Ruby, 36, with ex-girlfriend Kelly Emberg; Liam’s sister Renee, 31; and Sarah, 59.

It was a tense game with Celtic securing the win finishing 2-1 after the team scored two goals in three minutes in the first half, one being an own goal

Rod was suited and booted for the special occasion in one of his signature suits as he watched his club go head-to-head with Rangers for a chance of winning another Scottish Premiership title

He was also joined by rarely-seen son Alastair, 18, who was spotted in the stands intensely watching the game with his father

Celtic won thanks to two goals from Kyogo Furuhashi as well as a late penalty from Matt O'Riley.

This means they will go into the final on May 25 at least three points clear of rivals Rangers. 

Last month Sir Rod joined both sons Aiden and Alistair in Glasgow to see their team secure a place in the Scottish Cup final.

Sporting one of his signature snazzy looks, Rod and his boys watched on as Celtic stormed to victory, giving them the upper hand in the title race against their fierce rivals Rangers. 

It was a tense game with Celtic securing a win over Aberdeen in penalties 6 - 5 after the two sides drew 3 - 3 in the match.