Livingston picked up 10 points to secure their spot in the knockout rounds, while the Championship side racked up 11 points from their four group matches.
Match preview
Livingston made relatively light work of their group stage campaign, which began with a commanding 3-0 away victory over Brechin City.
A penalty shootout defeat to Hamilton Academical in their second match ensured Livington missed out on a bonus point, but wins over Cove Rangers and Clyde were ultimately enough to help David Martindale's side progress to the last-16.
Since wrapping up the group stage, they have experienced a difficult start to the Scottish Premiership season, picking up just one point from two tricky matches.
A goalless home draw against Aberdeen was followed by a heavy 4-0 defeat to Rangers, who scored three goals in the final 12 minutes of regulation time.
Following a humbling afternoon at Ibrox, Livington may be looking forward to turning their attention to Saturday's Scottish League Cup tie, where they will be attempting to reach the quarter-finals for the fourth time in five seasons.
Meanwhile, Ayr began their Scottish League Cup campaign with a 1-1 draw against Stirling Albion, but they managed to win the subsequent penalty shoot to pick up a bonus point.
They went on to edge out Stenhousemuir and St Johnstone, before thrashing third-tier Alloa Athletic 6-0 to round off the group phase in style.
After avoiding consecutive group stage exits, the Scottish Championship side are now tasked with eliminating top-flight opposition.
Incidentally, Ayr's most recent meeting with Livington took place at this stage of the Scottish League Cup, and it proved to be a forgettable experience as they fell to a 4-0 defeat.
If they are able to get the better of the side from West Lothian, it would represent Ayr's first quarter-final appearance since the 2018-19 campaign.
Livingston Scottish League Cup form:
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Livingston form (all competitions):
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Ayr United Scottish League Cup form:
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Ayr United form (all competitions):
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Team News
There are doubts surrounding the availability of Bruce Anderson and Scott Pittman, who both missed Livingston's defeat to Rangers through injury.
After being unveiled as a Livington player last week, Samson Lawal could be included in the matchday squad for Saturday's encounter.
Kurtis Guthrie dropped out of the starting lineup last weekend, but the 30-year-old is in contention to return for the Scottish League Cup tie.
As for the visitors, George Stanger will retain his place in central defence alongside Sean McGinty after the pair helped their side keep a clean sheet in Ayr's 1-0 win over Inverness Caledonian Thistle.
Aiden McGeady, who joined the club this summer, has featured as a substitute for the opening two league games, and the former Celtic winger could be utilised off the bench again, as he builds his way to full fitness.
Mark McKenzie is expected to resume his forward partnership with young striker Fraser Bryden, who has scored three goals in his four appearances in the Scottish League Cup this season.
Livingston possible starting lineup:
George; De Lucas, Obileye, Devlin; Brandon, Guthrie, Holt, Shinnie, Montano; Kelly, Nouble
Ayr United possible starting lineup:
Albinson; McAllister, Stanger, McGinty, Reading; Amartey, Smith, Dempsey, Ashford; McKenzie, Bryden
We say: Livingston 2-1 Ayr United
Ayr have already picked up a victory against a Scottish Premiership side on their travels this season after beating St Johnstone 2-1 in the group stage of the Scottish League Cup.
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