"The manager saw something in me and gave me a chance," says O'Brien
On the pitch, Aiden O'Brien has emerged as a crucial cog under Neil Harris; off it, he can often be found laughing and joking with teammates at the Calmont Road training ground.
The Official Millwall website spoke to him this week about positional changes, Sunday's Emirates FA Cup clash, and why he always strives to "play with a smile."
During his time at The Den, the versatile 23-year-old has been employed as a striker and, more recently, a winger.
And despite moving back and forth between positions this season he's enjoyed a fine spell in front of goal, scoring 11 times across all competitions.
"And i'm not finished yet!" O'Brien joked in an interview with millwallfc.co.uk.
"I feel it's a good achievement and I hope to keep it up during the second half of the season.
"The gaffer has tried me out wide and it took me a little while to come to grips with the move but i've warmed to the position.
"I just feel that he has seen something in me and that positional shift has paid off. He gave me a chance and I thank him for that."
Millwall are preparing to host Watford in the Emirates FA Cup, having produced one of the upsets of the Third Round with a 3-0 lashing of Premier League side AFC Bournemouth earlier this month.
"Before that match the manager told us to go out and express ourselves in front of our home fans.
"It's a great message to receive because it allows you to play with freedom and a smile on your face. We enjoyed that match, we worked together and expressed ourselves. If we can repeat that performance against Watford then it's going to be a good game."
The Lions are at long odds to spring a similar upset against the Hornets, something that's only fuelled determination to progress in the Cup.
"We are very confident in what we do and it doesn't matter who we play, be it Arsenal, Tottenham or Watford. It doesn't matter who we play, we always believe we can win," O'Brien added.
"These televised games are always special because it gives family and friends that don't live nearby the chance to watch us play. But we just have to treat this like another game and not let the occasion get the better of us because we want to progress."
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