Milos Raonic was back in action on the ATP Tour following his efforts in the South Pacific in January. Raonic failed to defend his Brisbane title down under and the Canadian also failed to duplicate his semifinal appearance at the Australian Open from the year prior. However, he is the top seed in Delray Beach this week and the Canadian got off to a strong start on Tuesday in the tournament's opening round.

Raonic won in straight sets

Raonic defeated American qualifier Tim Smyczek in straight sets 6-1, 6-4 in a routine match that only took 56 minutes for the Canadian to advance through.

The next round promises to be much more difficult as Raonic will face Borna Coric, the Croat, who pulled a win over Santiago Giraldo. Coric, who is 20 years old, is considered one of the brighter lights among the younger players on tour. Raonic will surely enter the match as the favorite, however a 6-1, 6-4 line score would be surprising for the Canadian in the next round.

Jack Sock defeated Radu Albot

On the other half of the draw, American player Jack Sock advanced through to the round of sixteen. Sock also had a pretty straight forward match as he defeated Radu Albot in straight sets, 6-4, 7-6. Sock might be America's best chance for a title in Delray Beach this week. He is the third seed in the event and his draw to the final is not beyond his capabilities by any stretch.

Next up, Sock will face Guillermo Garcia-Lopez, a Spanish veteran who defeated Dustin Brown on Monday.

Other Americans that have advanced so far include veteran Sam Querrey and newcomer Taylor Fritz. However, at time of writing the first round was not completed in Delray Beach. Donald Young, Steve Johnson, Stefan Kozlov, and Jared Donaldson all remained alive in the draw too.

As for non-Americans, Juan Martin del Potro is the biggest threat for a title this week. The former champion at the event and one-time US Open champion may collide with Milos Raonic in the semifinals this week, should neither player face an earlier round upset.