Once a month throughout the 2014 MLS season, MLSsoccer.com will take stock of the performances of rookie players, looking at which first-year professionals are making the biggest impact for their team and in the league.

We're now two months into the season and, to be honest, we are still looking for that "wow" moment when a rookie really makes us stand up and take notice.

It's hard to get too down on this year's rookie class, though. After all, Harry Shipp has developed into a realiable assist man for the Chicago Fire since claiming a starting spot on the second day of the season, which has also helped him hold his place atop the rankings.

As injuries, suspensions, poor play and international call-ups start to throw wrenches in various teams' carefully-laid plans, however, we can expect to see more and more rookies stepping up to solve those problems.

Perhaps the prime example is San Jose Earthquakes midfielder J.J. Koval, who has earned the trust of coach Mark Watson to the point that he has started back-to-back games after subbing on in the Quakes' first four MLS games. Koval first garnered attention when putting in a heroic defensive shift against Toluca in the CONCACAF Champions League in March.

The Montreal Impact's Eric Miller could be facing the opposite situation, as he lost his place in the lineup at the end of April. He should still see playing time, though, with MLS teams entering the Amway Canadian Championship kicking next week.

Jared Watts (Colorado Rapids) and Alex Martinez (Sporting KC) also look set for more playing time as rosters become thinner, having impressed in substitute appearances and facing the prospect of a busy summer schedule.

Finally, a tip of the cap and a message of condolence to Chivas USA midfielder Tommy McNamara, who tore his ACL in a game against Portland and looks set to miss the rest of season. He will not make the list but is still the only rookie to score so far this season, and you can bet we'll be looking for him in 2015.

Only MLS regular-season games reflected on schedule and statistics.

Rank Trending Last Player Comment 1 1 Harry Shipp The Fire Homegrown Player may not have played a full 90 minutes in the month of April but nonetheless remains a starter and retains the top spot after recording his third assist of the campaign in the team's final game of the month. Last Month: 4/5 vs. Philadelphia (2-2 tie, 57 min), 4/12 at Montreal (0-0 tie, 75 min), 4/19 vs. New England (1-1 tie, 70 min, 1 A)

4/5 vs. Philadelphia (2-2 tie, 57 min), 4/12 at Montreal (0-0 tie, 75 min), 4/19 vs. New England (1-1 tie, 70 min, 1 A) This Month: Saturday vs. Real Salt Lake (8:30 pm ET; MLS LIVE ), 5/10 at New York, 5/18 vs. Sporting KC, 5/24 at Columbus

Saturday vs. Real Salt Lake (8:30 pm ET; ), 5/10 at New York, 5/18 vs. Sporting KC, 5/24 at Columbus Season Statistics: 3 A (6 GP, 6 GS)

3 A (6 GP, 6 GS) MLS Fantasy Soccer Manager: 32 points, $6.0 million (12.7 percent owned) 2 5 JJ Koval The Earthquakes may have only played three games in April, but we got to see plenty of Koval during that time. He has forced longtime Ligue 1 veteran Jean-Baptiste Pierazzi out of a starting spot in the center of midfield and edges out Miller in the rankings by virtue of his strong finish to the month in two 90-minute outings. Last Month: 4/13 vs. Columbus (1-1 tie, 37 min), 4/19 at Colorado (0-0 tie, 90 min), 4/26 vs. Chivas USA (1-0 win, 90 min)

4/13 vs. Columbus (1-1 tie, 37 min), 4/19 at Colorado (0-0 tie, 90 min), 4/26 vs. Chivas USA (1-0 win, 90 min) This Month: Saturday at Vancouver (7 pm ET, MLS LIVE in the US, TSN2 in Canada), 5/7 vs. Colorado, 5/10 vs. FC Dallas, 5/17 at Seattle, 5/25 vs. Houston, 5/31 at FC Dallas

Saturday at Vancouver (7 pm ET, in the US, TSN2 in Canada), 5/7 vs. Colorado, 5/10 vs. FC Dallas, 5/17 at Seattle, 5/25 vs. Houston, 5/31 at FC Dallas Season Statistics: 295 min, 19 recoveries, 1 SoG (6 GP, 2 GS)

295 min, 19 recoveries, 1 SoG (6 GP, 2 GS) MLS Fantasy Soccer Manager: 10 points, $4.6 million (22.2 percent owned) 3 4 Eric Miller The Impact fullback was, until final game of the month, the only rookie to have started all of his team's games to date, but he found himself on the bench after Montreal conceded four goals in Kansas City. Still, he has logged by far the most minutes of any rookie and should remain a factor for the Impact in the season to come. Last Month: 4/5 vs. New York (2-2 tie, 90 min), 4/12 vs. Chicago (1-1 tie, 90 min), 4/19 at Sporting KC (4-0 loss, 90 min), 4/26 vs. Philadelphia (1-0 win, 1 min)

4/5 vs. New York (2-2 tie, 90 min), 4/12 vs. Chicago (1-1 tie, 90 min), 4/19 at Sporting KC (4-0 loss, 90 min), 4/26 vs. Philadelphia (1-0 win, 1 min) This Month: 5/10 vs. Sporting KC, 5/17 at D.C. United, 5/24 at Colorado, 5/31 vs. New England

5/10 vs. Sporting KC, 5/17 at D.C. United, 5/24 at Colorado, 5/31 vs. New England Season Statistics: 631 min, 2 SoG (8 GP, 7 GS)

631 min, 2 SoG (8 GP, 7 GS) MLS Fantasy Soccer Manager: 19 points, $5.0 million (20.2 percent owned) 4 N/A Jared Watts Showed his gritty side when he went the full 90 minutes and drew a red-card foul in Colorado's intensely physical 0-0 draw against San Jose. He may not start week in, week out, but it's easy to see him developing into a reliable bench contributor for Pablo Mastroeni's team. Last Month: 4/5 at Vancouver (2-1 win, 1 min), 4/12 at Toronto (1-0 win, unused sub), 4/19 vs. San Jose (0-0 tie, 90 min), 4/26 at Seattle (4-1 loss, 19 min)

4/5 at Vancouver (2-1 win, 1 min), 4/12 at Toronto (1-0 win, unused sub), 4/19 vs. San Jose (0-0 tie, 90 min), 4/26 at Seattle (4-1 loss, 19 min) This Month: Saturday vs. LA Galaxy (9:30 pm ET, MLS LIVE ), 5/7 at San Jose, 5/11 vs. Chivas USA, 5/17 at Real Salt Lake, 5/24 vs. Montreal

Saturday vs. LA Galaxy (9:30 pm ET, ), 5/7 at San Jose, 5/11 vs. Chivas USA, 5/17 at Real Salt Lake, 5/24 vs. Montreal Season Statistics: 200 min, 1 SoG (4 GP, 2 GS)

200 min, 1 SoG (4 GP, 2 GS) MLS Fantasy Soccer Manager: 10 points, $4.8 million (2.8 percent owned) 5 N/A Alex Martinez Speaking of bench contributors, this Sporting KC youngster has looked more than capable in his three substitute appearances to date. Expect to see plenty more of the attack-minded midfielder as Sporting kick off a summer slog that starts with seven games in May and will likely see players depart for the World Cup, not to mention eventual participation in the US Open Cup and CONCACAF Champions League. Last Month: 4/5 vs. Real Salt Lake (0-0 tie, unused sub), 4/19 vs. Montreal (4-0 win, 14 min), 4/26 at New England (2-0 loss, 32 min)

4/5 vs. Real Salt Lake (0-0 tie, unused sub), 4/19 vs. Montreal (4-0 win, 14 min), 4/26 at New England (2-0 loss, 32 min) This Month: 5/4 vs. Columbus (4 pm ET, NBCSN), 5/10 at Montreal 5/14 vs. Philadelphia, 5/18 at Chicago, 5/23 vs. Toronto, 5/27 vs. New York, 5/31 at D.C. United

5/4 vs. Columbus (4 pm ET, NBCSN), 5/10 at Montreal 5/14 vs. Philadelphia, 5/18 at Chicago, 5/23 vs. Toronto, 5/27 vs. New York, 5/31 at D.C. United Season Statistics: 61 minutes, 2 SoG (3 GP, 0 GS)

61 minutes, 2 SoG (3 GP, 0 GS) MLS Fantasy Soccer Manager: 3 points, $4.1 million (7.8 percent owned)

Other rookies to watch: , Marlon Hairston (Colorado Rapids), Kris Tyrpak (Chivas USA), Mark Sherrod (Houston Dynamo), Nick Hagglund (Toronto FC), A.J. Cochran (Houston Dynamo)