It's hard to believe it, but there has officially been a full month of baseball. While a month might be too early to, say, tab the currently reigning Kansas City Royals as the "team to beat" in the AL Central, it is a reasonable period of time to react to rookies' performances.

Out of spring training, there were five notable prospects who, for one reason or another, were able to win a spot on their respective organization's major league rosters. Below is a pulse check on how those five are currently performing.

  • Jackie Bradley Jr.

    Boston Red Sox

    With David Ortiz still ailing from an off-season Achillis' injury, the Boston Red Sox needed an offensive boost. Jackie Bradley Jr., the Red Sox's top outfield prospect, took advantage of the situation. Bradley raked a .419/.507/.613 line over 72 PAs during spring training, earning not only a roster spot with the major league team, but also the starting left field gig too. However, after posting a dismal .097/.263/.129 line over 38 PAs, the 23 year-old was optioned to Triple-A on April 18.

  • Aaron Hicks

    Minnesota Twins

    Like Bradley, Aaron Hicks won a starting outfield job with the Minnesota Twins due to an incredible spring training. The 23 year-old posted a .370/.407/.644 line over 79 PAs, displacing Darin Mastroianni as the Twins starting center fielder. But the top prospect hasn't exactly wowed in the big leagues. To-date, even though Hicks is still on the major league roster, he's only hit a .120/.230/.160 line over 87 PAs. The Twins have apparently given Hicks a long leash as the former first round pick continues to be the starter.

  • Jedd Gyorko

    San Diego Padres

    Jedd Gyorko was on every fantasy owner's "sleeper list"--which sort of made him the anti-thesis of a sleeper. Gyorko had everyone drooling over his .333/.400/.552 line with 25 HR and a .311/.373/.547 line with 30 HR in 2011 and 2012, respectively. Yet, due to Chase Headley's stronghold on third base, Gyorko--a natural third baseman--was without a true position. However, when both Headley and Logan Forsythe fell prey to injury, Gyorko finally got his shot. Starting at second base for the San Diego Padres, the 24 year-old has been solid, posting a 94 OPS+ over 107 PAs. But despite those two monstrous home run seasons in the minors, Gyorko only has 1 dinger to-date.

  • Evan Gattis

    Atlanta Braves

    Atlanta Braves fans were sorry to see long time back up catcher David Ross depart this off-season--only because starter Brian McCann was primed to miss a significant amount of time. New backstop Gerald Laird didn't do much in spring training to inspire confidence (.154/.241/.308 line over 29 PAs), which paved the way for Evan Gattis. Gattis, who plays outfield and first base in addition to catcher, has immediately become a fan favorite in Atlanta. Stepping in for the injured McCann, the 26-year-old Texas native has owned a 125 OPS+ with 6 HR and 16 RBI. Even though the hitter hasn't walked much (6.8% BB%), fans have been impressed enough with the catcher to outwardly wonder if McCann should be given his starting job back.

  • Brandon Maurer

    Seattle Mariners

    With pitching prospects like Taijuan Walker, Danny Hultzen, and James Paxton in the Seattle Mariners' farm system, it's easy to forget about Brandon Maurer. Yet, unlike the Mariners' supposed top three pitching prospects, Maurer was the only one to actually crack the major league squad's rotation. The right-handed pitcher enjoyed a solid season at Double-A in 2012, hurling a 3.20 ERA, 1.31 WHIP, and 2.44 K/BB over 137.6 IP. But as great as Maurer was during spring training (1.50 ERA, 1.25 WHIP, and 3.57 K/BB over 24 IP), the 22 year-old hasn't been particular sharp through his first six outings. In fact, the former 22nd rounder has pitched to the tune of a 6.07 ERA, 1.44 WHIP, and 2.25 K/BB. As if Maurer's high-ERA wasn't telling enough, his 62 ERA+ pretty much paints how bad the pitcher has been in 2013.