And having waited so long to claim his maiden scalp, he unfurled a stirring, double-fist pump celebration well worthy of the occasion.
Given his chance in the Adelaide Strikers starting XI for the first time this season, after the defending champions' first-choice seamers Peter Siddle and Billy Stanlake were called up for national ODI duties, Agar was understandably nervous.
Especially when Strikers skipper Travis Head asked his young quick to bowl the fifth over of the innings, as the Melbourne Stars headed in hot pursuit of the host team's daunting total of 5-178.
Before a crowd of more than 30,000, on a breathlessly hot Adelaide evening, Agar could not have dared imagine a more inauspicious start.
With Stars openers Evan Gulbis and Ben Dunk at full-throttle during the last over of the Power play, the right-armer coughed up 17 runs from his first four deliveries including an audacious six beyond the third-man rope by Gulbis.
At that point, Agar's BBL career figures stood starkly at 8.4 overs, 0-112 and he briefly feared his chances of adding a 10th over to that aggregate were looking shaky.
But with the luxury of additional fielders outside the perimeter circle, Head threw his young charge the ball for the eighth over of the innings, with the Stars flying at 2-53.
"I've made a knack of going for about 16 off my first over, but I'm just in a really good state mentally, was really calm and had a good plan," Agar said in the aftermath of the Strikers' clinical 41-run win.
"So I backed myself in to come back, and do well once we had the five (fielders) out.
"I was a bit nervous, but I think those (nerves) went away once I started bowling."
The doubts briefly resurfaced when Gulbis belted Agar's second delivery of his new spell to the mid-wicket boundary.
But the trusted plan to which the bowler reverted saw him angle the next delivery into the Stars' opener, who swung lustily once more and had his off-stump rattled.
The roar that Agar unleashed at the sight of the zing bails lighting up for the first time in his BBL bowling career was only interrupted by a sudden dread that he had over-stepped, and that his great moment might be rendered an anti-climax.
"I actually looked back at the umpire to check it was not a no-ball," Agar said of his maiden wicket.
"So you see me do a big 360 (degree turn), but it was raw emotion and that was what came out.
"I was just really excited.
"I've been running the drinks, and watching the (Strikers) boys do what they do, seeing the boys go up to Australia (to the ODI squad) and getting my chance.
"I just really wanted to do well, and to get that wicket was just really special to me and really important.
"So it felt really good."
Having grown up in Melbourne, Agar moved to Adelaide in 2015 after being signed to a rookie contract by the West End Redbacks.
His hope was to push for first-class selection, a bold move given the depth of seam bowling options in SA with the likes of Chadd Sayers, Daniel Worrall, Joe Mennie, Kane Richardson and Nick Winter.
After a stint in which he played in the domestic one-day cup competition as well as Toyota Futures League and Premier Cricket, Agar returned to Melbourne's first-grade competition last summer seeking further opportunities.
He had made his first appearance for the Strikers in January 2017, and despite being part of their championship-winning squad last year he played just one game in BBL|07 – against the Perth Scorchers, whose XI included his older brother and Australia spinner, Ashton Agar.
But last night at Adelaide Oval, it was the younger Agar taking the spotlight.
In addition to his animated wicket celebration, which he unleashed for a second time when he trapped Stars' youngster Jason Merlo lbw in the 14th over to all-but seal his team's win, Agar attracted attention for his new haircut.
A no-back-nor-sides look topped by a luxurious covering of hair, that has won approval from his elder brother who has taken to the clean-shaven look in recent years.
The younger Agar admits his new do is not so much a fashion statement as an admission he had run out of ideas, and left the decision as to how it should be shaped in the hands of a barber.
"I just thought I'd go something different," Agar confessed.
"It was a Sunday and I just went down to the hairdressers and said 'sort me out and give me whatever you want' and that's what came out.
"I don't mind it though, the brother doesn't mind it so I'll just rock it for now."
Top bowling from @MrT tonight!— Adelaide Strikers (@StrikersBBL) January 11, 2019
Whoops, we mean Wes Agar 🤦♂️
He finishes his four overs with figures of 2/33 in his first match of #BBL08 😁 #BlueEnergy #TerriblePhotoshopsOfTheBBL pic.twitter.com/flHCqfGsYl