De Villiers struck a blazing 99 and then picked up 2 wickets with his medium pace to steer Proteas, who were coming off a shock loss to Pakistan in their previous match. The South Africans are now second in the pool led by India, who still have a match to play against Zimbabwe. Teams:
However, the final standings will only be known after the Pakistan-Ireland and West Indies-UAE clashes on Sunday.
Striking his second fifty of the tournament, de Villiers jumped to the second spot in the run-scorers list, behind Kumar Sangakkara, as South Africa amassed 341 for six in their stipulated 50 overs after being put into bat first.
Coming in at number seven, batsman Farhaan Behardien (64 not out) also played a crucial knock and stitched up an unbeaten 49-run seventh-wicket partnership with Vernon Philander (10 not out) to give Proteas the necessary fillip in the end overs.
The South African bowlers were also clinical in their showing as Morne Morkel, Vernon Philander and de Villiers shared two wickets apiece to bundle out UAE for 195 in 47.3 overs. UAE's No.11 Fahad Alhashmi was unable to come out on the field due to injury.
UAE were never in the chase as they lost wickets at regular intervals with wicketkeeper-batsman Swapnil Patil (57 not out) and Shaiman Anwar (39) providing the only bit of resistance in an otherwise lackluster showing.
South Africa batsmen, on the other hand, were a complete contrast with a concerted effort from the top, middle and the lower-order.
Quinton de Kock (26) and Rilee Roussow (43) stitched a 68-run second wicket partnership though the innings wobbled after the wicketkeeper-batsman's departure in the 19th over.
De Villiers, whose 82-ball stay was laced with 6 fours and 4 sixes, then managed a 108-run fourth wicket stand with David Miller (49) to give the inexperienced UAE bowlers a hard time.
De Villiers though was unlucky to miss out on his second ton of the tournament after being scalped by new-ball bowler Kamran Shazad. Then Behardien smacked his way to his third ODI fifty-- a 31-ball cameo laced with 5 fours and 3 sixes.
UAE pace spearhead Mohammad Naveed bagged 3 wickets while Shazad, Amjad Javed and skipper Mohammad Tauqir also chipped in with a wicket each.
Earlier, De Villiers once again proved to be the crucial cog for the Proteas, who have endured an unexpectedly wobbly campaign so far.
However, the prolific right-hander missed out on a hundred by a solitary run even though he walked back with a smile on his face after being caught by Javed at third man.
Later, Behardien played out a sensational knock to propel the South Africans to a mammoth total.
The South Africans were off to an edgy start with Amla and de Kock failing to provide a solid platform for the middle order. But Rossouw (43 off 49 balls, 4x8) lent some stability before de Villiers took it upon himself to rescue the side yet again.
The dashing batsman combined with Miller to help South Africa recover from a rather precarious 96/3. The duo took the team total past 200 before Miller was castled by Naveed after a 48-ball stay, during which he struck two fours.
De Villiers made his way back after taking the side past 250. The South Africans capitalised on the momentum provided by de Villiers through Behardien, who finally came good after an indifferent campaign so far.
South Africa: Hashim Amla, Quinton de Kock, Rilee Rossouw, AB de Villiers (capt), Jean-Paul Duminy, David Miller, Farhaan Behardien, Vernon Philander, Dale Steyn, Morne Morkel, Imran Tahir.
United Arab Emirates: Amjad Ali, Andri Berenger, Khurram Khan, Shaiman Anwar, Swapnil Patil, Saqlain Haider, Amjad Javed, Mohammad Naveed, Mohammad Tauqir (capt), Fahad Alhashmi, Kamran Shazad.
De Villiers struck a blazing 99 and then picked up 2 wickets with his medium pace to steer Proteas, who were coming off a shock loss to Pakistan in their previous match. The South Africans are now second in the pool led by India, who still have a match to play against Zimbabwe.