BY 9.0 in the Limerick Gaelic Grounds on Sunday evening, there was clear evidence that one swallow doesn't make a summer. Instead, the deserted stadium had become a feeding ground for at least a dozen of the splendid creatures, swooping low across the surface in the slanting sun before spinning acrobatically towards the smiling blue skies.
It was as if they were celebrating events of a few hours earlier when Limerick did the hurling championship an enormous service by beating Tipperary. Nothing against Tipp, but any early-season upset would have been welcome in order to whip the competition out of its perceived predictability.
Limerick disrupted the Munster scenario and, while Kilkenny are still driving on in Leinster, their four-goal spill against Offaly sent opposition hearts beating a little quicker. Any sign of weakness in a big beast, however temporary it might be, is always welcome in the jungle, so the sight of Kilkenny goalkeeper Eoin Murphy retrieving the sliotar from the net four times will have encouraged others.
It had only happened twice before in Brian Cody's 63-game championship term (v Galway in the 2005 All-Ireland semi-final and v Tipperary in the 2010 All-Ireland final). The difference was that whereas Kilkenny lost those two games, they won last Sunday. Still, Cody will have his plumbers checking for the source of the leaks before greater pressure is added to the flow later on.
Limerick's win has left Tipperary perusing the 2010 All-Ireland route map, which they negotiated so successfully after an even earlier Munster setback (back then they lost in the quarter-final as opposed to the semi-final last Sunday), and the likelihood is that they will be major influences again at the business end of this summer.
For now, though, it's all about Limerick and the shot of encouragement they have injected into hurling's power grid. The impact of Sunday's win extended beyond Limerick, initially north into Clare and south into Cork before stretching elsewhere too.
It means that the Munster title will be heading for either Limerick (after a 17-year gap), Clare (15 years) or Cork (seven years). And while Dublin and Wexford have their own business to conduct on Saturday evening, they too will be encouraged by Limerick's success, which was a considerable boost for Division 1B.
One of the comfortable consensus views holds that there's a significant gap between 1A and 1B, and that operating in the lower group in spring leaves counties at a considerable disadvantage in summer.
In fairness, it's a theory that 1B counties have been happy to indulge as defence mechanisms when the championship sends them down bumpy roads. Poor us, we've been stuck in 1B all spring.
There's no doubt that the lower end of 1B is a long way off 1A pace. Not so at the top end of 1B, as Limerick proved conclusively, having given a fair indication of the same last season when they led Tipperary by seven points in the Munster quarter-final before losing out on the home stretch.
As manager John Allen pointed out, a big difference between this year and last year was that when Limerick looked to their bench to bolster their efforts in the second half against Tipperary, their resources were much stronger this time.
There's a sense of genuine delight for Allen that he has masterminded a really significant win for Limerick, one that offers real hope for the future. Allen isn't into gimmicks, smart put-downs or sullen responses on days when Limerick lose.
Instead, he is always pleasant, patient and honest in his assessments. That included last Sunday when he admitted that there were times in the run-up to the game when he wondered if Limerick would be "beaten out the gate".
Outside of the Limerick camp itself, this was also a huge result. The atmosphere in the closing minutes was fantastic as Treaty County supporters got behind the team in a very spirited way. No doubt, the win will encourage a whole lot more Limerick people to climb aboard from now on.
At a time when rugby is so strong in Limerick, the return of the hurling team as a major power would be a real plus for the GAA in the county and indeed beyond.
While Limerick still have a long way to go, they are on the right road and can clearly see the signposts, leading towards bigger destinations.
As for Tipperary, they will be fine too.
And hurling? It had a very good day last Sunday.