World ranking: 12
US Open best:
2001: 3rd round
2000: 3rd round
The tall Dutchman reached the last four at Flushing Meadows last year - the highlight of his career so far.
He put out players of the calibre of Mark Philippoussis, Gustavo Kuerten and Fernando Gonzalez before being beaten by eventual winner Pete Sampras.
In doing so Schalken became the first Dutchman to reach the semis of the US Open since Tom Okker in 1971.
That run at the US Open, followed by a final in Moscow, helped Schalken to finish the year ranked 20th in the world.
And he has continued to progress since then, reaching a career-high 11th in the rankings in April this year.
Schalken may not be the most elegant of players - few look as awkward from the back of the court - but he is strong off both sides and has a huge serve.
He has endured a pretty miserable run on hard courts this summer but has the stamina required to prosper in Grand Slam events, and is sure to be a tough opponent at Flushing Meadows.