Shane Duffy admitted that he "had goosebumps" after making his home debut for the Republic of Ireland.
The Blackburn Rovers defender made his second senior appearance for the Boys in Green in their 1-0 win over Switzerland at the Aviva Stadium on March 25 and was named 'Man of the Match' after a 90 minutes which saw him grab an assist and a clean sheet.
The 24-year-old made his debut for Ireland against Costa Rica in the summer of 2014, but says that he was "more ready" to play senior international football this time round.
"I was more ready for it now than I was two years ago when I played," Duffy told reporters after the game. "I enjoyed it, playing in front of Irish fans for the first time was enjoyable, and I had goosebumps out there. It was a day I dreamed of, and I've got it."
"I'm playing more regularly and consistently. I've matured as a centre half," continued the former Everton defender.
"The more games you play, the better you get. I was quite raw two years ago, I still am, but I'm playing every week and I'm enjoying it. I'm delighted to come here, and just trying to impress the manager and the players."
Noticeable features of Duffy's performance against Switzerland were his presence and leadership qualities. At six foot four he is a commanding figure in the backline and Duffy says that he tries to be a vocal communicator.
"I try to get in the game. I try to be a leader," explained the defender. "It helps with good players in front of me. I'm quiet off the pitch but I try to be vocal on it. I'm just happy we got the clean sheet and the win."
Duffy's maturity in what was only his second senior international appearance has caught the attention of former internationals such as Keith Andrews and Kenny Cunningham as well as former Ireland boss Brian Kerr, who wrote in his Irish Times column that "the Derry man...was the most positive return from this friendly" and gives O'Neill "food for thought".
The centre back played down his chances of making the final 23-man squad for Euro 2016 but hinted that "you never know" in football.
"We just have to try and go out there and do what we can do and impress the manager. I try to go out there and enjoy playing for Ireland," said Duffy.
"It's only one game, but it was good. [Ciaran Clark] plays on the left and I play on the right. Listen we've got so many good centre-halves here, it's hard to even get close to the squad so I'm delighted to be here. You never know.
"Everyone wants to play, but the lads who got us to the Euros, they've done all the hard work, so you can't just expect to come in.
"I'll bide my time and if it's not this one, then it's the next campaign. I've just got to focus on club football, and try to impress. If that does it, then I've got to come in and put in a performance."
Duffy could have another chance to impress O'Neill in Tuesday's friendly against Slovakia and he is hopeful that he may feature again.
"After that you just want to go again," he said. "I didn't want it to end to be honest, I was just enjoying it. I wish we played better the second half, but defensively I'm happy.
"Tuesday you never know, but there's a lot of centre-halves."