Munster took full advantage of the red card shown to Racing Metro flanker Antoine Battut to earn a convincing 29-6 triumph over the French Top 14 side. The win, which featured a hat-trick of tries from flying winger Simon Zebo, helped Munster maintain their hopes of collecting one of the two best runners-up spots in the race to reach the quarter-finals.
"We were up against some pretty resilient opposition and the boys delivered a pretty compelling performance at times," Penney said. "We made a couple of errors early on and that was on the back of being a bit anxious and wanting to do well. It took us a bit of time to settle into the game, probably longer than we would have liked."
He added: "Once we got into our rhythm, I thought at times we were compelling. We looked very efficient. Our mental preparation and ability to stay focused for the whole 80 minutes was something we were going to need today. The relentlessness we were seeking was there."
New Zealander Penney said reaching the quarter-finals of the Heineken Cup was important in terms of the side's development.
"If we hadn't (reached the quarter-finals) the people would be in the long grass, there would have been a lot of bullets being fired," Penney said.
"If we hadn't gotten the outcome today, I would have been still proud of the progress we are making and the areas of growth we are getting. I really believe in this team and the direction it is going."
Penney agreed that the early dismissal of Battut, who seemingly aimed a knee at the head of Tommy O'Donnell, had a major influence on the outcome.
He said: "I haven't really seen the incident which led to the red card. The referee saw something there and adjudicated based on what he saw.
"Without doubt it had a bearing on the game. Any time you lose a player and are down to 14, you are up against it. When it happens early on it makes a massive amount of workload for the other 14 guys on the park."
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