
Logan Chalmers was influential throughout, scoring the hosts' second
Partick Thistle set up a Premier Sports Cup quarter-final tie at home to holders Celtic by easing aside lacklustre Ayr United at Firhill.
Daniel O'Reilly's looping header gave the hosts a deserved lead and Logan Chalmers' powerful drive doubled the advantage before half-time.
Fitzpatrick slid a second-half effort wide as the hosts continued to dominate and ultimately breezed past a toothless United side.
These sides have been tipped to challenge at the top of the Championship this season, and on this showing it is Thistle who look the more capable.
Mark Wilson's men started positively with a succession of drives forward from the lively Chalmers, setting the tone for the composed and attacking display that was to follow.
Aidan Fitzpatrick's low effort cracked off the post before the attacker had a close-range goal ruled out for offside.
Ayr were struggling to cope with Thistle's relentless attacks, and Robbie Crawford and Tony Watt had attempts dealt with inside the area.
A whipped Chalmers corner then found O'Reilly who looped a header back across goal and into the net, leaving Ayr goalkeeper David Mitchell helpless.
Chalmers received the ball out wide just before the interval, bounced it off Tsoanelo Lets'osa, and drove goalward before firing in form 20 yards with a powerful low strike.
- Published17 August
What they said
Partick Thistle manager Mark Wilson: "The team played well and controlled the game, should have been more, and delighted to get through.
"Tsoanelo Lets'osa has been a breath of fresh air since he came in. He brings so much energy, and you can see what a player he is. He was terrific today.
"It was great, everybody was at it, and that's what we asked. I thought we were brave on the ball.
"It ended up comfortable, and if I'm nitpicking, [Aidan] Fitzpatrick has a couple of chances and Tony [Watt] has a really good chance, and we could have made it a more comfortable scoreline."
Ayr United manager Scott Brown: "An injury early doors [to Shaun Want] never really helps, but it's more personal pride than anything, you've got to turn up, win battles, and have desire, they had more desire today, which was a little bit disappointing.
"You can see their front three's willingness to run but also to do their defensive duties, that's where we slacked off a little bit.
"We didn't threaten their goal. [We made] poor decisions on the ball today.
"It's a disappointing performance overall. I take the blame, I've got to take the blame, I put that team out."
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