Karlovic Loses in the First Round at Delray Beach Open

The defending champion, eleminated in the first round

Ivo Karlovic wasn't sure he could or should try to defend his title at the Delray Beach Open. An old knee injury had flared up during the Australian Open last month, forcing the 36-year-old Croatian to retire from his first-round match and sidelining him from the practice courts ever since.

Though Karlovic gamely tried to serve his way past 27-year-old qualifier John-Patrick Smith of Australia, his rust was evident and the third seed was ousted 6-3, 3-6, 6-2 in the opening round on Monday night.

The win was just the fourth main draw match victory of Smith's career and his second-best win. A four-time All-American at the University of Tennessee, Smith upset No. 25 Bernard Tomic en route to the semifinals at Newport last year.