Here are VAVEL USA's weekly risers and fallers for the fifth week of the 2015 MLB season, May 4-10.

Risers

Bryce Harper, Washington Nationals: Harper was incredible this past week, batting .455/.520/1.318 with six home runs, a double, and 13 RBI in six games. His six home runs came over the course of three days, including a three-home run game and a two-home run game in consecutive games. He then hit a walk-off home run the next day.

Michael Pineda, New York Yankees: Pineda pitched a league-most 15 innings last week with a 0.60 ERA and 22 strikeouts over two starts. His 16-strikeout game on Sunday with no walks was just the 22nd time the feat has been achieved, and the first time since Johan Satnana did so in 2007.

Felix Hernandez, Seattle Mariners: Hernandez posted a 1.93 ERA in 14 innings last week with 14 strikeouts. His strikeout of Sam Fuld was his 2,000th career strikeout, making him the fourth-youngest pitcher to achieve the feat, and just the sixth active pitcher.

Alex Rodriguez, New York Yankees: Rodriguez makes the Risers list for the second straight week as he hit his 661st career home run offf of Chris Tillman to pass Willie Mays and take sole posession of fourth on the all-time home run list.

Marlon Byrd, Cincinnati Reds: Byrd played only five games last week, yet he still had four multi-hit games and three home runs. Despite this being in his 14th season, Byrd does not appear to be slowing down anytime soon.

Fallers

Josh Harrison, Pittsburgh Pirates: Harrison is in a major slump, making the Fallers list for the second week in a row. He followed up last week's 1-for-23 performance by going 1 for 14 with a strikeout. Harrison is now batting .173 this season with as many strikeouts as hits.

Jarrod Parker, Oakland Athletics: Parker left his Minor-League rehab game this past week after suffering a fractured right elbow. He will likely need surgery along the lines of Tommy John, which he was rehabbing from. Parker has already undergone Tommy John twice in his career.

Tampa Bay Rays' pitching staff: It was reported last week that Alex Cobb (Tommy John surgery) and Drew Smyly (Torn labrum) would be out for the season, becoming the 9th and 10th players on Tampa Bay's disabled list. They join pitchers Jake McGee, C.J. Riefenhauser, Jeff Beliveau, and Matt More on the DL.

Boston Red Sox' pitching: The Red Sox' pitching staff posted a fourth-worst 5.16 ERA, raising their combined season ERA to a terrible 4.97, better than only Colorado's 5.47. Boston also fired their pitching coach Juan Nieves in an attempt to change the momentum of the staff.

Colorado Rockies: The Rockies went 0-4 last week, having three games rained out, to extend their losing streak to nine games. This is the longest losing streak so far of the season, and they will look to snap it on Tuesday against the Los Angeles Angels. Colorado's pitching staff was also by far the worst last week, posting an 8.26 ERA, more than two runs higher than the second-worst team. They also had a league-worst .329 batting average against in the four games they played.