The Albion defender helped loan club St Pauli keep a clean sheet in a 2-0 home win over arch-rivals Hamburg SV, the club’s first victory over their city neighbours for 59 years.
He said, “It was fantastic and definitely the best atmosphere I’ve ever played in. It was a bit of shock for me because it’s a huge derby game.
“I’m 19 and still relatively new to the club so I had to just try to do my best and not think about everything around the game, but of course it was superb, and everything was so memorable.
“You have to be there to really get a feel for how crazy the fans were. It’s a new step for me and now I know how it feels to play in front of 30,000 passionate fans. I’ll learn a lot from that and it’s exactly what I need at this stage of my career.
“It was a really fun game to play in. It’s the first win at home for the club against Hamburg so it’s historic. It’s always good to be part of history, now for me it’s about working hard for more appearances.”
The Norwegian under-21 international also reserved special praise for the impressive support from the club’s renowned fanbase – at both the Millerntor-Stadion and on the road.
“The fans are amazing, I’ve never experienced anything like it. When you see and witness it live then you get an idea,” he continued.
“Even if you have a heavy defeat they’re always with you, home games are always packed, and they travel with good numbers. Our away ends are always full.
“You can see how much it means to them. The derby game was massive, and they’ll be happy for the rest of the season now because we won.
“They want to win that game more than anything, it’s fantastic to be a part of this. The fans are everywhere. In pre-season the away games were full as well and they’re so passionate here.”
The game marked Ostigard’s second league appearance since making the loan switch in July, and he now hopes to put a frustrating start to the season behind him.
“The minutes were important because I had a little injury at the start of the season.
“I played one game in pre-season then picked up a knock, but the full 90 minutes on Monday was a big thing for me. Now I’ve had the chance and I feel I’ve taken it.
“Everyone was happy for me because they know what I can do for the club, it’s important you make the most of the opportunities and are ready when they come around.
“The fact it was a derby meant it had an edge to it, but I always believe in my ability here and trust I can help the side.”
The central defender has familiar company at St Pauli in the form of fellow Albion teammate Viktor Gyokeres, and as he also revealed, a fellow countryman too.
“It’s a really nice city and I have an apartment here now. Of course, I have Viktor [Gyokeres] close by and we were close at Brighton, so that always helps too.
“We have a good relationship because we speak the same language. He will start playing soon and he knows he has to take his chance. This level is good for him also and it will improve him as a player too.
“There’s a Norwegian here in Mats Moller Daehli and he’s been fantastic. It’s good to have people you know to help you if things aren’t as easy in the beginning, but everyone’s been great.”
The German Bundesliga 2 contains the likes of Stuggart, Hannover, Nurnberg, and the aforementioned Hamburg, and Ostigard has been impressed with the intensity he’s experienced in the division so far.
“The league is really competitive. The football is quite direct, and we press quite high.
“We move forward up the field fast and do a lot of running, we want to attack and excite people and it’s good to be a part of.
“You have to adapt to that and be in good shape physically. They are hard matches where you run a lot so that’s the biggest difference compared to where I’ve been before.
“I want to keep getting more minutes and play as many games as possible. I came here to play, and I think I have the ability to be able to do that.
“It’s about improving every day and showing people what I can bring to the team. This level will raise my game and make me better without a doubt.
“I’m happy to be here and just want to keep showing my qualities.”