Following the end of his playing career, which was followed by a period working in the insurance industry, Ingleby-Mackenzie assumed the presidency of the Marylebone Cricket Club (MCC) between 1996 and 1998.
[2][3] He was educated firstly at Ludgrove School, where the ex-Yorkshire cricketer Alan Barber was headmaster,[4] before attending Eton College.
[8] The following season, he made six first-class appearances for Hampshire, playing five County Championship matches, and once against the touring Indians.
[7] After completing his education at Eton, Ingleby-Mackenzie gained a place at Trinity College, Oxford, but chose not to matriculate.
After completing his National Service, Ingleby-Mackenzie gained employment with Slazenger in Yorkshire,[6][10] who provided him with copious leave to pursue a parallel cricket career with Hampshire.
He established himself in the Hampshire side as a middle order batsman in the 1954 season, making 29 first-class appearances,[7] scoring 821 runs at an average of 17.84.
[12] The tour took place in March and April 1956, with Ingleby-Mackenzie playing two first-class matches against Trinidad and a West Indies XI.
He made a maiden first-class century with an unbeaten 124 runs against Oxford University,[14] in what was his first match of the season for Hampshire.
[2] 1958 also coincided with a change of professional career for Ingleby-Mackenzie, with him being co-opted by the Kent cricketer Bryan Valentine into the insurance brokers Holmwoods, Back and Manson.
"[4] With the likes of West Indian opening batsman Roy Marshall and the fast bowlers Derek Shackleton and Butch White, he possessed a team which could back up his risk-taking captaincy.
John Arlott said the book "reflects a considerable capacity for the enjoyment of most pleasures... [and] presents a picture of a young man engagingly carefree in a way that seems to belong to a different age from ours".
[7] He led Hampshire to a tenth placed finish in the 1963 County Championship, though played in only nineteen first-class matches during the season.
His absence was caused by an illness he had picked up in Australia during the winter, but had not fully recovered from, necessitating rest and recuperation in August.
[21] Earlier in the season, he had the distinction of captaining Hampshire in their inaugural List A one-day match against Derbyshire in the Gillette Cup, with Ingleby-Mackenzie keeping wicket in place of regular wicket-keeper Brian Timms.
[26] Ingleby-Mackenzie retired, aged just 31, following the 1965 season;[27] the last amateur to captain Hampshire, he passed the captaincy onto the professional Roy Marshall.
[30] During this two-year tenure as president, he oversaw the approval and initial stages of construction of the futuristic media centre.
[31] As president, he initiated reforms to allow women to be elected MCC members,[6] seeking to rid the club of "a fuddy-duddy image of old men puffing on pipes".
[35] He became cricket manager for his friend Sir Paul Getty at his ground at Wormsley, where he was responsible for arranging fixtures, raising teams, and leading tours.
[36] Amongst his closest friends were the actors Albert Finney, John Standing, Edward Fox, and the comedian Ronnie Corbett.
[41] For his funeral, the hearse carrying his coffin passed beneath and adjacent to the stands as it circled Lord's before making its way to Kensal Rise Crematorium.