McGrath, 37, who started the tournament 10 wickets behind the Pakistani, took the new ball for the first time in the tournament in a match reduced to 22 overs a side after a five-hour delay.
He equalled Akram's record when he bowled Shahriar Nafees for one in his second over then set the new mark of 56 in his following over when Aftab Ahmed was athletically caught by Nathan Bracken at mid-on for 11.
McGrath, who will retire from all cricket after the World Cup final in Barbados on April 28, has taken more than 360 one-day wickets for his country and has the best World Cup analysis of seven for 15 against Namibia.
His pinpoint accuracy and forensic ability to detect any weaknesses in his opponents' armoury have made him an integral member of the Australia side since he played a major part in their series victory over West Indies in 1995, the first loss by the host side for 15 years.
Immaculate line&length McGrath's forte: Bowl straight and move the ball away late from the batsman have been instructions handed down by generations of cricket coaches to pace bowlers.
But few have followed them quite so thoroughly as Australia's Glenn McGrath who on Saturday beat Wasim Akram's record of 55 World Cup wickets.
The New South Welshman, who will retire from international cricket after the World Cup, has been renowned throughout his career for his remorseless accuracy and fondness for publicly targeting opponents' key batsmen.
Yet away from the field, the 37-year-old is said to be a much quieter, reserved man.
Born in the country town of Dubbo, New South Wales, McGrath lived in a caravan when he first came to Sydney to try to make it in state cricket.
He soon worked out a method that would help him become the most successful fast bowler in Test history.
Realising he would never be as fast as a Dennis Lillee or Jeff Thomson, McGrath settled instead for the disciplines of line and length.
Although not the quickest, McGrath was soon developing the ability to move the ball away at a sufficiently sharp pace to trouble the world's best batsmen.
Called up by Australia in 1993 as a replacement for Merv Hughes, McGrath never looked back and became a key member of one of the most successful cricket teams of all time.
In particular he was soon making a speciality of claiming the wicket of Michael Atherton in Ashes contests at a time when the opener was England's batting rock.
McGrath's accuracy proved a particular asset in one-day cricket.
He helped Australia reach the 1996 World Cup final, where they lost to Sri Lanka, before starring in their victorious 1999 and 2003 campaigns, the last featuring a record-breaking seven for 15 against minnows Namibia.
There were doubts about his future when he returned from ankle surgery in 2004 and two years later when he returned from a break when he was looking after his wife, Jane, who has suffered several bouts of cancer.
And it is his wife's health and a desire to spend more time with their children that have sparked his retirement.
Only occasionally have McGrath's boasts not been backed up by events. Before the 2005 Ashes he predicted a 5-0 whitewash for the men in baggy green caps. Instead England won the series 2-1.
In common with many other quicks, McGrath's age has been held against him the longer his career has gone on and he was one of the "Dad's Army", England great Ian Botham had in mind when he taunted the Australians about the several '30-somethings' in their squad ahead of the last Ashes campaign.
McGrath, who by then had long since surpassed West Indian Courtney Walsh's mark of 519 Test wickets, responded with 21 wickets at an average of 23.90 as Australia regained the Ashes 5-0.
And on his home Sydney Cricket Ground, McGrath bowed out of Test cricket by taking a wicket with his last ball when he dismissed James Anderson.
That left him with a Test record of 563 wickets from 124 matches at 21.64.
But perhaps even more indelible was the attitude displayed by McGrath, who occasionally would stand with hands on hips and pass a comment or two to a batsman who'd had the temerity to hit him for four, and fellow bowling great Shane Warne who also retired from Test cricket after the Sydney Ashes clash.
"He's a very proud man, Glenn," Australia captain Ricky Ponting told reporters here Friday.
"He actually had a dig at me the other day for not bowling him at the tail against the West Indies because he wanted a couple more wickets.
"When it's big game time it's generally the Warnes and McGraths and those sorts of guys that really stand up."
But few "guys" rank alongside the Australian duo.