Leinster head coach Matt O'Connor felt his side should have made more of their opportunities during the first half of their 19-7 Heineken Cup victory over Castres Olympique.
A 62nd-minute try from replacement prop Jack McGrath, after Castres lost centre Remi Lamerat to the sin-bin, proved crucial at the RDS but the French side were less than an inch away from taking home a losing bonus point.
Pedrie Wannenburg thought he had crashed over for a try with two minutes left on the clock but TMO Graham Hughes went against the former Ulster flanker.
It was left to fly-half Jimmy Gopperth, who kicked four penalties and a conversion, to steer Leinster home with some fine tactical kicking behind the swarming Castres attackers.
McGrath's big moment arrived on the hour mark as he dived over for his first Heineken Cup try near the posts leaving Castres, who were 9-7 down at half-time, with nothing to take home from Dublin.
A relieved O'Connor said afterwards: "I certainly think we got out of jail with regard to them getting nothing (no bonus point). I don't think we got out of jail with regards to the result.
"In the first half we were, by far, the better side. They got a lucky score and we didn't capitalise on our opportunities. They came back hard in the second half but we'll take the four points."
Fergus McFadden and Kevin McLaughlin, both of whom were making their 100th provincial appearances, were exposed on the blindside for Rory Kockott's opportunist try, but O'Connor argued, 'it was nobody's fault'.
"The ball skews out the side (of the scrum)," the Australian said, "and two quality players (Antonie Claassen and Kockott) execute on the short side to give them seven points.
"Thankfully, they didn't get anything else.
"Castres are a quality side. They are physically massive as a group.
“You don't fluke it and win the Top 14 unless you've got a really good squad. We put a lot of holes in them but didn't capitalise.
"It is one of those things. You take the four points and make sure we are better next time."
Referring to Wannenburg's close call with three minutes left on the clock, O'Connor conceded: "It wasn't a great camera angle and you couldn't really tell as you couldn't see it being scored.
“You'd have to ask the guys out there but it wasn't obvious on camera."
Castres captain Remi Tales sought to take positives out of his team's defeat.
"We held our own against a really good team," he said.
"We must remember this game and how well we played, when we face them again at home in January."