Trott (79 not out) missed out in the Lions’ first-innings 443 all out but, in just his second time in England colours since the stress-related issues which afflicted him in the 2013 Ashes tour, he made no mistake.
He and debutant Sam Billings (53) were to the fore in a century stand as the tourists augmented their lead early, before an afternoon declaration on 176-5.
Trott left his bowlers a scheduled 56 overs to see off their inexperienced hosts, and the Lions were on track until an approaching electrical storm brought a tactical retreat and early close after Gauteng had stumbled to 120-8 in 42.
Set a purely notional 441 to win, the hosts were soon in trouble again against the Lions’ five-strong seam attack.
Jonny Bairstow’s athleticism behind the stumps gave his Yorkshire team-mate Jack Brooks (1-16) the first success, a catch down the leg-side accounting for Yassar Cook.
Yorkshire pair Liam Plunkett (1-22) and Adil Rashid (2-14) also got in on the act, while their county colleague Alex Lees – who scored 85 in the Lions’ first innings – made a one-handed catch at mid-wicket off Adam Riley before the weather intervened to save the hosts.