Red Sox, Pirates and Royals might have staying power, other things we learned in April

The first month of the season is coming to a close, and here are things we can take away from April:

* There's no need to panic when a team goes bad for a week. Last week, the Nats were struggling and on the verge of falling into a big hole in the NL East. But they won three weekend games against the Reds, and with the Braves getting swept in Detroit, things are calmer in the division. If the Nats had continued to play inattentive baseball and had the Braves not cooled down, the Nats could have been facing an eight-game deficit going into this week's series in Atlanta.

The Braves' problems have been a lack of timely hitting - 39 strikeouts in the Detroit series - and bad defense. They are coming home after a never-ending trip to Pittsburgh, the cold of Denver and the rain of Detroit. Justin Upton's home runs are getting attention for the Braves, but another player Atlanta acquired in that trade with Arizona, third baseman Chris Johnson, goes into Monday night with the National League's highest batting average.

* The Red Sox have staying power. Yes, they beat up on the lowly Astros over the weekend, but they have a club-record number of wins during April, and John Lackey's strong six-inning performance Sunday gives them four solid starters. Jon Lester and Clay Buchholz have returned to their 2011 form. Ryan Dempster is pitching well, but doesn't have wins to show for it, and Lackey, who hasn't had much to feel good about in his time in Boston, is healthy mentally and physically. Felix Doubront is a developing prospect that is going to have good and bad times.

* The Tigers have found bullpen stability. Jose Valverde is back for the Tigers, who no longer have to use a bullpen-by-committee. Valverde has been a dependable closer in Detroit, but after a bad postseason in 2012, the Tigers decided not to sign him. Their 21-year-old prospect, Bruce Rondon, was supposed to win the job, but lack of command pushed him to the minors. Valverde signed a minor-league deal, pitched a couple of games at Single-A, and now hasn't allowed a base runner in his first three games. The big difference in Valverde from last fall: He's got a better splitter.

* The Royals will be a factor. For years, the Royals have been trying to fix their rotation. This year, it looks like they've done it. Of their top four starters, Wade Davis' 3.20 ERA is the highest. The rotation is piling up innings - James Shields has gone six, six, nine, six and eight innings in each of his first five starts. Jeremy Guthrie has gone at least six in each of his five starts, and former Angel Ervin Santana has gone six once, seven and eight twice each.

* The Pirates are survivors. With three games against opponents with losing records, April was supposed to be a tough month for the Pirates. Instead, they've made a statement in the NL Central, even though it has been a tough month for their most recognizable superstar, Andrew McCutchen. Outfielder Starling Marte, who hit .442 during a 10-game hitting streak, and pitcher Jeff Locke, who has 13 consecutive scoreless innings, have been productive rookies. Locke had trouble in early April, but after he figured out the importance of first-pitch strikes, he's been on cruise control.