"Fear not, for e'er this day is done, you shall have a hole-in-one..."
John Steed plays Golf in five The Avengers episodes:

The Medicine Men (Season 3), The Murder Market (Series 4), The Thirteenth Hole (Season 4), at the end of Take-Over (Season 6) and TNA Angels of Death.

Steed's handicap in The Medicine Men is 24, while Cathy's is only 12. Mrs. Peel's handicap in The Thirteenth Hole are handcuffs.

His "caddy" is a Fairy Godmother - Mrs. Peel in The Thirteenth Hole.

John Steed invents "Indoor Golf" in The Medicine Men and "Invisible Golf" in Take-Over and his golf techniques are ... unique.
He played indoor golf with his bowler and Mrs. Gale.
Steed played with two of his partners golf: Mrs Gale and Mrs. Peel. He did not play with Tara, but practiced indoor golf in Tara King's flat in Take-Over and in his mansion in TNA Angels of Death when Mike Gambit was there.
Steed's practises some unorthodox methods to get a birdie or an eagle and is driving his opponents crazy. The enemies try to kill him with a golf ball, but he's well prepared wearing a hat lined with chainmail.
Steed playing indoor golf and invisible golf
His way playing golf in The Thirteenth Hole is the worst nightmare for every groundskeeper of a golf green.