Park knows what it's like to carry the expectations of a nation in Europe, having become United's first Korean player when he arrived from PSV in 2005.
Similarly, Kagawa will be the Reds' maiden Japanese signing and he, too, is making the switch from another European club in Borussia Dortmund.
"I know United have agreed a deal for Kagawa and I'm happy because we're signing a good player," Park told ManUtd.kr at an event hosted by his JS Foundation.
"Manchester United is a huge club and every season, we sign new, world-class names. I hope Kagawa shows how good he is next season and I think he will do."