What we learned from the first month of the baseball season

The first month of the baseball season is in the books. The first checkpoint has arrived, and so here's what you need to know about April's developing stories.

* The Trevor-ending story: Sorry to start with a bad pun, but who could resist? And who would have thought that Colorado shortstop Trevor Story's home runs would be all the rage after the first month? He has 10 going into the week, including five in Arizona and four at the Rockies' Coors Field. In an unusual scheduling twist, the Rockies have already made two trips to Arizona this season. Maybe the Diamondbacks should trade for Story?

* The Orioles' Joey Rickard isn't the only Rule 5 draftee sparking a team from the leadoff spot. Center fielder Odubel Herrera, 24, is part of the reason Philadelphia is off to a winning start. Herrera was taken in the December 2014 Rule 5 draft from Texas. Last season, he had a .396 on-base percentage after the All-Star break. He goes into this week with 23 walks and a .449 on-base percentage. Last year, he had 28 walks with 495 at-bats. The Phillies, meanwhile, have back-to-back sweeps - of the Nationals and Cleveland - and have had a strong April, thanks to the growth of young pitching such as Aaron Nola and Vince Velasquez.

* The Orioles and Blue Jays are expected to battle it out in the American League East and each team has a chance to lead the league in runs scored and/or home runs. But look out for the Red Sox: They lead the AL with 14 10-hit games. David Ortiz is the first 40-year-old in history to have at least five home runs and 11 doubles in April. Jackie Bradley Jr. is coming on with 41 of his last 70 hits going for extra bases. Bradley and fellow outfielder Mookie Betts have each hit two triples in a game during April, the first time a team has done that since the 1962 Cardinals. ... And the Red Sox's pitching is coming around. Starter David Price and closer Craig Kimbrel have rebounded from slow starts. Reliever Carson Smith, acquired in Seattle, and Eduardo Rodriguez, arguably the Red Sox's best pitcher last season, are on rehabilitation assignments and will join the team soon.

* Seattle is another surprise team in the AL, considering the Mariners started the season 2-6 and finished April 13-11. Felix Hernandez (1.38 ERA) and Taijuan Walker (1.80 ERA) are leading a rotation that has five games where starters allowed zero runs, including starts by Wade Miley and Nate Karns. The Mariners are winning with home run power and expect more runs when Robinson Canso (.237), Adam Lind (.227) and Kyle Seager (.163) start hitting. Even though he's not hitting for average, Cano has eight home runs and 24 RBIs.

* Arizona added two top-of-the-rotation pitchers in the offseason, but has started slowly because Zack Greinke and Shelby Miller have not done well. Greinke, 32, has given up 47 hits in 37 innings, although he pitched well over the weekend. Miller, 25, has had command issues with 19 walks and 19 strikeouts, unusual for a pitcher that's had ERAs of 3.05, 3.74 and 3.02 in the previous three seasons.

* What's going on with the Dodgers? Over the weekend, they lost a series to the division-rival Padres. Previously, they had won nine consecutive series against San Diego. But the Dodgers are mess. After a fast start, Chase Utley is slowing down, probably more in line with the fact that he's 38. Yaisel Puig is slumping, and so is Howie Kendrick. Left fielder Carl Crawford has seen his better days. The Dodgers hope that shortstop Cory Seager and centerfield Joc Pederson can help for a core of young players. And, the pitching, beyond Clayton Kershaw and Kenta Maeda, is struggling. Scott Kazmir is off to a bad start. Alex Wood is a No. 3 starter at best.

* While Arizona is the disappointment in the National League, the Houston Astros are the disappointment in the AL. The Astros are scoring runs, but their rotation has been bad: Even though Dallas Keuchel, the 2015 AL Cy Young Award winner, isn't a high-velocity guy, his velocity is down and the Astros are concerned. Lance McCullers, a rookie last season, is rehabilitating a sore shoulder. And the rest of the rotation members - Scott Feldman, former Nat Doug Fister and Collin McHugh, a 19-game winner last season - are giving up too many walks and each has allowed more hits than innings pitched.

* Prospect Blake Snell of Tampa Bay made his big league debut for the Rays last week and became the 11th big-league pitcher to have a single-digit number: Snell is No. 4. The others include Rob Bell (6), Kyle Drabek (4), Carl Edwards (6), Wayne Gomes (2), Mike Leake (8), Ron Mahay (3), Adam Ottavino (0), Marcus Stroman (6), Josh Towers (7) and David Wells (3).

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