"I'm very happy I won,'' Korolev said. "Every tournament you play you hope to win it. This is the first time I'm in the final.''
Korolev was the second consecutive qualifier to secure a final berth at this tournament. Kei Nishikori of Japan did not attempt to defend his title this year.
The 105th-ranked Korolev was the fourth qualifier to reach the Delray Beach final. Besides Nishikori, Alex Calatrava of Spain was a finalist in 2000 and Andrew Ilie of Australia won in 1998.
"I just know that Nishikori was coming out of the qualis last year and I'll be happy to do the same thing,'' Korolev said.
Korolev, a first cousin of former player Anna Kournikova, was the first Russian to reach the Delray Beach final in the tournament's 16-year history.
Korolev pummeled 60th-ranked Rochus in the first set with his heavy groundstrokes, particularly off the forehand.
In the second set, Korolev jumped out to a 5-2 lead and served for the match at 5-3. Rochus took advantage of a brief letdown by Korolev to hold serve at love in the eighth game and to break in the ninth game, but couldn't push his way into a third set.
Korolev will play the winner of the semifinal between top-seeded Mardy Fish of the United States and seventh-seeded Jeremy Chardy of France.
Korolev makes first career final at Delray Beach
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