O'Brien came on to bowl in the 49th over with Zimbabwe requiring 9 runs from 12 Balls and 3 wickets in hand.
His first ball was a full toss but Zimbabwean captain Prosper Utseya hit it straight to Eoin Morgan at cover to give him his first World Cup wicket.
Chris Mpofu was run out off O'Brien's final delivery and he finished the penultimate over with a wicket maiden.
Ireland came up against Pakistan in the next game and they restricted the Test nation to just 132 with O'Brien taking the wicket of Shoaib Malik.
O'Brien came in to bat with his side at 70/4 and he added 38 runs with his brother Niall.
Ireland eventually won by 3 wickets and O'Brien finished unbeaten on 16 from 52 Balls.
His highest score of the tournament came in the Super Eight stage against New Zealand where he made 49, hitting 3 sixes.
He missed out on his half century when he was run out by his brother.
1952
Ireland then took on Canada and O'Brien continued his good form with the bat by making his 3rd consecutive score of fifty plus with a composed 52.
The final game of the tournament came against the Netherlands and despite failing with the bat he took 2 wickets.
He finished as the second top scorer in the League with 263 runs at 52.80.
1984
Kevin Joseph O'Brien (born 4 March 1984) is an Irish former international cricketer who plays for Leinster and Railway Union Cricket Club.
On 16 August 2022, he announced his retirement from international cricket.
2004
Kevin O'Brien represented Ireland in the Under-19s World Cup of 2004 in which he made 241 runs to help his country reach the Plate Semi-Final before being defeated by Australia Under-19s.
The following year he played for the MCC Young Cricketers.
2006
He made his One Day International (ODI) debut in 2006 in Ireland's inaugural match.
In June 2006, he made his One Day International debut in Ireland's inaugural ODI game, against England in Belfast.
Bowling first he took 1 for 47 off his 10 overs as England managed 301.
His wicket came off his first delivery and was that of captain Andrew Strauss who was caught at square leg by Andre Botha.
Batting at number 8, O'Brien made 35 from 48 Balls but Ireland fell 38 runs short.
In Ireland's disappointing World Cricket League campaign in Kenya, O'Brien was one of the success stories.
In their second game of the tournament, against Bermuda, O'Brien took his career best figures of 2 for 38 by taking the wickets of middle order batsmen David Hemp and Lionel Cann.
In the chase he made 54, his maiden ODI half century and helped his side win with 8 Balls to spare.
When Ireland made 284 batting first against Kenya in the following game it was O'Brien who made half of the runs.
His innings of 142 was the highest ever by an Irish batsman and was made off 128 Balls, containing 10 fours and 6 sixes.
2007
The next tour for O'Brien was the 2007 World Cup in the Caribbean and it would be his biggest test yet as 6 of his 7 One Day International games prior had been against non-Test playing nations.
Their opening game against Zimbabwe finished in a tie when Zimbabwe collapsed in the dying stages.
2009
O'Brien played for Nottinghamshire in 2009, and in 2010 was awarded a contract with Cricket Ireland, making him one of six players with a full-time contract with the board.
He was the first player for Ireland to take 100 wickets in ODIs.
2011
He scored the third fastest century in 50-over World Cup, coming from 50 Balls against England on 2 March 2011.
2018
O'Brien was one of the eleven cricketers to play in Ireland's first ever Test match, against Pakistan, in May 2018, scoring the first Test century for Ireland men's cricket and becoming the first sportsperson from Ireland to represent his country in 300 matches.
O'Brien is an aggressive right-handed middle to lower order batsman and a right-arm medium-fast bowler.
In December 2018, he was one of nineteen players to be awarded a central contract by Cricket Ireland for the 2019 season.
2020
In January 2020, he was one of nineteen players to be awarded a central contract from Cricket Ireland, the first year in which all contracts were awarded on a full-time basis.
In June 2021, O'Brien announced his retirement from ODI cricket, to allow him to focus on T20 and Test cricket.
Kevin O'Brien was educated at Marian College, Ballsbridge.
He has a degree in marketing and advertising.
His brother Niall was also a member of the Irish team.
Their father Brendan played 52 times for Ireland.
His sister, Ciara, played for the Irish women's hockey team.
