Each week, the Sports on Earth staff presents the greatest sports performances we can find anywhere in the world. But only one will be declared "Top Athlete On Earth" each week.

Given that this past week brought with it the opening round of the Stanley Cup Playoffs and the NBA postseason, there were plenty of strong candidates. Montreal Canadiens right winger Alexander Radulov turned his team's fortunes around against the Rangers, scoring the Game 2-winning goal -- in OT, no less -- and added a goal and an assist in Game 3 as his team took a 2-games-to-1 series edge. That same day, Penguins rookie Jake Guentzel completed a hat trick against the Blue Jackets, and one of his three goals proved to be the game winner in OT, making the 22 year old the NHL leader in postseason goals this season.

And although their seasons are just beginning, Giants outfielder Jarrett Parker and Marlins shortstop J.T. Riddle also merit honorable mentions. Parker went all out to catch a deep fly ball at San Fran's AT&T Park, crashing into the outfield wall and breaking his collarbone in the process. The rookie Riddle fared a bit better, launching a walk-off two run shot against the Mets for his first career home run.

And now for the Top 5.

5. Katherine Switzer

Back in 1967, Switzer registered to run the Boston Marathon under the name K.V. Switzer, becoming the first official female entrant in what was then an all-male race. Now 70, Switzer completed Monday's race -- her first attempt at the 26-mile course since 1976 -- with an official time of 4:44:31.

4. Isaiah Thomas

Just one day after his 22-year-old sister, Chyna, tragically died in a car accident, Celtics point guard Thomas did something that takes an incalcualable amount of heart and bravery: He took to the court for Game 1 of the playoffs against the reigning champion Cavaliers. Thomas, who averaged 28.9 points per game during the regular season, sank 33 that night to lead the team.

3. Yoenis Cespedes

In the span of just three games, slugging Mets outfielder Cespedes notched five of his six home runs to date this season. On April 11, he made history against the Phillies when he recorded the second three-homer game of his career. Two days after his club's 14-4 romp, Cespedes enjoyed a two-home run showing against the Marlins.

2. Pekka Rinne

The Nashville Predators entered their playoff series against the Chicago Blackhawks as unambiguous underdogs, but thanks to goalie Rinne, they now possess a 3-0 series advantage. Rinne shut out the Blackhawks in the first two games and ultimately allowed just two goals in 95 attempts through the first three contests for a minuscule 0.61 goals against average.

And the winner is...

1. Manuela Schar

Paralympian Schar of Switzerland set a world best mark as she won the women's wheelchair division of Monday's Boston Marathon -- her first victory in the race -- with a time of 1:28:17, making her the first female ever to top 1:30. Schar's counterpart, Marcel Hug, also set a course record in the men's wheelchair division.