Leicester Tigers left the Madejski Stadium with the aura of a side that fully expects to be challenging for Aviva Premiership honours this season.
They picked up a dramatic bonus-point win when winger Niall Morris scored their fourth and final try with just 52 seconds left on the clock.
Every game is a tough one in this season's Premiership, but the really good sides would expect to come here and win.
Tigers did that by only playing well for 55 of the 80 minutes. They scored their four tries with a sumptuous blend of raw power and silky skills.
Their scrum rode roughshod over the Exiles pack in the opposition 22 and picked up another two penalty tries.
Out wide, Morris scored two tries and would have had a hat-trick had he not be taken out off the ball as he was about to touch down.
Leicester's backs looked dangerous and pacey as a unit behind the organisation of fly-half Toby Flood, who was making his first appearance for the club in eight weeks.
There was no hint of rustiness. Flood looked confident, perfectly in control and was the orchestrator of both of Morris' scores.
He was perfect with the boot, apart from one long-distance kick that hit the crossbar.
"The bars are a lot thinner at Welford Road," he joked after the game.
He also nailed an absolutely crucial long-distance penalty on 67 minutes, which not only put Leicester two scores up at 17-9, it also ended the momentum of an Exiles side who were mounting an unlikely recovery after being dominated in the first-half.
Tigers made a cracking start and were 7-0 up on 11 minutes. Flood saw Morris in space out wide as he was thinking about a penalty kick and unloaded a beautifully-weighted cross-field kick to the Irishman.
Morris took the ball at pace, skipped past two defenders and dived over the line under the tackle of Tom Homer.
It was 14-0 on the half-hour when referee Luke Pearce awarded a penalty try as Tigers pack dominated a series of scrums near the home side's line.
Tigers were so much on top at this stage against an Irish side in 11th place and low on confidence that it seemed the game was already won at half-time, despite former Tiger Ian Humphreys getting his team on the board with a penalty just before the interval.
But, like they had done against Treviso at Welford Road a fortnight earlier, Tigers completely lost their grip on the game and put in their sloppiest 25 minutes of the season.
Ben Youngs was sin-binned for tackling Darren Allinson too early after a tap-penalty, and Humphreys quickly pulled it back to 14-9.
Leicester were getting turned over in the tackle, slicing clearance kicks and passes were going to ground as they lost all sense of structure.
They also got broken at the gain line and one particular break by Jonathan Joseph looked certain to put Irish into the lead until Geordan Murphy scrambled over to make the tackle.
Make no mistake about it, these were worrying moments.
Flood's 68th-minute penalty took the sting out of the hosts and then the game was ended when Jamie Gibson took out Morris as he was about to touch down following a lovely chip-and-chase on 73 minutes.
Tigers were awarded a second penalty try and Gibson was sent to the cooler.
Then Morris wrapped up the bonus point by touching down with just 52 seconds left after latching on to Flood's break.
Few other clubs, if any, would come away from the Madejski Stadium with a bonus-point win and be as harsh on themselves as Leicester were after the whistle.
But letting a strangled animal to escape has become a bit of a theme of the season.
Allow a Saracens or Harlequins team off the hook at the business end of the season and they will surely be made to pay for it.
For 25 minutes, they were sloppy, unco-ordinated and allowed an Irish team that was ready to be put to the sword, back in the game.
They are the phases of play that need to be stamped out if Leicester are to win the Premiership title come late May.