A redoubtable and remarkably consistent centre-back for Liverpool for 10 straight seasons, he has been propelled at warp speed to the dilemmas of management, having assumed the top position in this corner of North Rhine-Westphalia after only six games as a 'trainee' and one season as caretaker alongside Sascha Lewandowski.
Scotching suggestions that he was too cold, too much of a block of Scandinavian ice to be an effective mentor for young players, he has steadily transformed perceptions of his personality. "I'm finding my way a little bit," he admits. "But when I get angry, I can be very loud. It's not like I am always peaceful."
Hyypia's restoration to Old Trafford on Tuesday promises to be a poignant one. After all, the last time he was there, he was the linchpin of a Liverpool side who grasped a memorable 4-1 victory in 2009.
"Yeah, those were my last 90 minutes in a Liverpool shirt and we managed to win 4-1," he recalls. "I wasn't even supposed to start. Álvaro Arbeloa was injured in the warm-up and only two minutes before kick-off did I knew I was playing. So from that point of view it went quite well."
It must be a trait of the Finnish temperament to convey understatement in such endearingly deadpan style. "We have fiery characters but the country is too cold in the winter to be warm-blooded," Hyypia says, smiling. "It is typical me."
Such sangfroid ought to be a virtue when he emerges at United in his touchline suit, into the teeth of a vitriolic reception reserved only for alumni of the loathed Merseyside enemy. For a decade he entered this cauldron as a player and it will be peculiar, he acknowledges, to approach the occasion without the spectacle of Sir Alex Ferguson in the home dugout.
"It's strange, knowing that he was there for so long and suddenly he is not. But I guess we all get older." Hyypia, plainly, is not one to accept the limitations of age, seizing his opportunity at Leverkusen within two years of retiring as a player.
Extraordinarily, throughout all those obdurate performances at the heart of Liverpool's back line, he never once suffered a serious injury setback. "Not one," he confirms, proudly.
"I feel very happy and lucky about that. I believe always in hard work I had to, from a young age, to improve. I always had that mentality, that when I took to the pitch I wanted to learn something new or to improve myself. If you are ready to do that, and if you want it so much, then it's possible to stay at the top for quite long.
"When I was younger I wasn't the biggest talent, and I felt that individually, there were a lot of better players than me. But I am a team player. That was the key to why I was at Liverpool for 10 years."
He claims he had never countenanced being a coach until the Leverkusen offer came, and still shuffles uneasily when asked if he has found a level of comfort in the job yet. "I don't know if comfortable is the right word," he says.
"As a player it was much easier. You came to training half an hour before, somebody told you what to do, and after training you headed to the shower and went home. Now you have to plan, instruct, think constantly about the next day, the next week, the next game. It's wonderful that I was given this case. I didn't expect it, and everything happened very quickly."
So fast, indeed, that Hyypia finds himself facing off against Pep Guardiola at Bayern Munich, and confronting his Champions League baptism as manager against David Moyes's United.
Already his Leverkusen team are building, though, upon last season's third-place Bundesliga finish with four victories in their first five matches, and his decision to shoulder the stresses of leadership is one he has not regretted for an instant.
"If I still played in the third division in Germany, then that would take some glory away from the good times," he argues.
"That is why I didn't do it. I find that I don't miss training and playing at the top level. Now if I play, I only do so for fun. But I always want to win." Never more, one senses, than on Tuesday.