Centuries yet again for Malcolm Waller and Regis Chakabva ensured Zimbabwe stayed in the ascendancy.
Resuming on 292 for 6, Ireland lost Kevin O’Brien (27) and George Dockrell (0) early, while Andy McBrine made 14.
John Mooney’s defiant 30 was ended by a stupendous running catch by Mamhiyo – one of four wickets for Garwe (4-61) – as Ireland were dismissed for 353.
With a 39 runs lead, former YMCA and CIYMS player PJ Moor went on the attack striking 8 boundaries in a whirlwind 41 from just 28 deliveries.
Kevin O’Brien (2-34) struck twice to slow the Zimbabwean onslaught, but Waller and Chakabva resumed where they left off in the first innings with another huge partnership.
They added 199 for the 4th wicket in 269 balls with Chakabva scoring 101 from 133 balls (8 fours, 1 six), and Waller again top scoring with 118 from 166 balls (10 fours, 3 sixes).
Their stand was ended when Chakabva was run out from midwicket by Niall O’Brien – Gary Wilson donning the gloves in the second innings.
George Dockrell(2-62) got the welcome wickets of Waller and Mamhiyo late in the day as Zimbabwe finished on 320 for 6.
A tough day again for the Irish, but with their batting quality on an excellent track they will confident of securing a draw.
ZIMBABWE A v IRELAND
Day 3 of 4,
At Harare Sports Club,
ZIMBABWE A 392 all out and 320/6 (67 overs, M Waller 119. R Chakabva 101, PJ Moor 41, K O’Brien 2-34, G Dockrell 2-62)
IRELAND 353 all out (95.4 overs, S Poynter 125, G Wilson 47, A Balbirnie 44, J Mooney 30, K O'Brien 27, N O'Brien 21, P Stirling 20, T Garwe 4-61B Vitori 3-63)
Zimbabwe A lead Ireland by 359 runs with four wickets left - continues Tuesday at 9am (BST).