Shenwari, who had been positively pedestrian for his first 40 runs, was dismissed for 96 after leading his side’s chase to 211 runs to victory.
UAE looked on course to record their first win over a test nation in their 20th official one-day international until Williams and Ervine intervened.
Martin Guptill and Daniel Flynn battled hostile pace bowling to guide New Zealand to 65 for no loss at the close of play on the third day on Sunday.
The Proteas say they will not lose sleep over two controversial umpiring decisions made on the first day of their final Test against the Black Caps.
New Zealand were 137 for two chasing 401 in the first test against South Africa when bad light stopped play four overs early on the fourth day.
The Proteas were beaten by six wickets after Martin Guptill’s return to form buoyed New Zealand in their Twenty20 international.
New Zealand winger Zac Guildford scored four tries as the All Blacks lifted the dark pall over their Cup campaign with a 79-15 victory over Canada.
Tonga produced the upset of the Cup when they beat France 19-14 on Saturday but poor decision making cost the Pacific Islanders at least five tries.
Italy illustrated the benefits of playing international rugby by beating Russia 53-17, while Pacific island players were in hot water with officials.
Bakkies Botha will almost certainly miss SA’s rugby World Cup opener, with the Springboks further hurt by an injury concern over winger Bryan Habana.
After a poor Tri-Nations campaign, the Boks are under increasing pressure as the president orders the World Cup home and fans hope for their success.
Springbok coach Peter de Villiers says there were no selection issues as John Smit is "the best hooker in world rugby".
The Reds’ victory can be seen as a portent of what is to come in just under two months when the World Cup begins in New Zealand.
The Auckland Blues head into the final round of matches on a four-match losing streak and need to beat the Otago Highlanders next Friday.
All Blacks and Crusaders captain Richie McCaw will miss the first month of the Super 15 rugby season after fracturing a bone in his foot.
New Zealand retained the Bledisloe Cup and all but secured the Tri-Nations trophy with a 20-10 victory over Australia at Lancaster Park on Saturday.
New Zealand secured their second successive bonus point win of the 2010 Tri-Nations with a 31-17 victory over South Africa on Saturday.
New Zealand continued their long unbeaten run at Eden Park with a controlled and aggressive performance to record a 32-12 victory over SA.
Venus Williams continued her domination of Francesca Schiavone on Monday, coming back from a set down to defeat the Italian 3-6, 6-2, 6-1.
World number one Serena Williams exudes a supreme confidence on the tennis court that could be deemed as a sign of an intense ruthless streak.
