The striker joined from Dunfermline Athletic this week for a fee of £60,000 on a two-year deal.
The move will give the 26-year-old his first taste of Cymru Premier football after leaving the Scottish Championship and McManus insists the ambition among the TNS hierarchy was a major factor in his move.
He said: "The manager had been watching me for a while and they got in touch with my agent, who called a couple of weeks later and said the opportunity was there if I wanted it.
"I was still in contract so I knew there would probably be a fee involved, so I wasn't overly optimistic that it would come about. I thought there would be a stumbling block somewhere.
"I'm absolutely delighted that, first of all, the club showed the ambition to come and get me and also Dunfermline were really good in letting it happen, once I'd spoken to the manager and chairman here.
"Their ambition is there for all to see and for me it was a big point in coming here.
"I want to come and win trophies. I want to win the big games and try and take the club as far as we can in Europe as well.
"That was a massive point for me coming here. Personally I want to come here and score as many goals as possible to help achieve all their goals.
"That's my job, I'm paid to score the goals. I have inside pressure on myself to make sure I do that.
"I always want to go out of my comfort zone and not get too comfortable. I want to achieve more, do better and strive to be better every week."
McManus also admitted he was 'oblivious' to the TNS interest in him at first but maintains that he always keeps his standards high to earn every opportunity in football.
"Every game you have to be at your best and give 100 per cent, because you never know who's watching," McManus added.
"Somebody might be there watching and it could be your next opportunity and path in football.
"That's one thing I always do, make sure I give 110 per cent."
McManus has already begun training with his new team-mates and revealed he needed to 'brush up' on his knowledge of Welsh football after making the switch.
"I had relative knowledge of it, but I won't lie and say I knew everything because I didn't," he said.
"The last few seasons TNS and Connah's Quay have been playing in the cup in Scotland and I'm a football geek, so I like to know about several leagues.
"I know of most of the clubs, I had relatively good knowledge before coming but I've been brushing up the last few days as well."