Armed with baseball's best rotation, Nationals are No. 1 for 2015

The No. 1 team heading into the 2015 season, the Nationals have gigantic expectations thanks to their super rotation and one of baseball's deepest and best lineups.

This week, SI.com is previewing all 30 MLB teams, counting down to the No. 1 team in the league. At No. 1: the Washington Nationals.

2014 Record and Finish: 96–66 (.593), first place in NL East (second overall)

2015 Projected Record and Finish: 99–63 (.611), first place in NL East (first overall)

The Case For

It’s World Series or bust in the nation’s capital. That much is clear after the Nationals—who won 96 games last year and led all of baseball in ERA—went out and signed one the best pitchers on the planet, Max Scherzer. After another heartbreaking October exit, Washington clearly isn't messing around: With the addition of the 2013 AL Cy Young winner, the Nats have, on paper, the best rotation in baseball. But let’s talk first about the offense, which gets overshadowed by the starting staff.

Sports Illustrated's 2015 MLB season preview rankings

Here’s the thing: the offense was good last year, ranking third in the NL in runs scored and fourth in OPS, but this year it could be really good. Anthony Rendon became an All-Star in his first full season, and this year the 24-year-old second baseman could be a top-three MVP candidate. Any year now, Bryce Harper is going to have a monster season, and 2015 looks like it could be it. Ryan Zimmerman’s move to first base, meanwhile, may help him improve at the plate. It’s a lineup with upside, one in which five hitters—Harper, Rendon, Jayson Werth, Ian Desmond and Zimmerman—could easily hit 20-plus home runs. Fear the pitching staff, but don’t forget about this team’s ability to light up the scoreboard.

Of course, there’s that all-universe rotation. All you need to know is that Doug Fister made 25 starts with a 2.41 ERA (fourth-best in the league) and threw seven shutout innings against the Giants in the NLDS, and he’s now the fifth starter. It's likely that Scherzer, Stephen Strasburg and Gio Gonzalez all improve from the years they had in 2014. Scherzer, who posted a 3.15 ERA and 252 strikeouts, should see his numbers benefit from the move to the NL (and a better defense behind him).

Strasburg cut down on his walks and topped 200 innings for the first time in his career, so '14 was a big one for the righthander, but there is a sense that the 26-year-old is still harnessing his stuff and that the best is yet to come. Gonzalez is healthy after an up-and-down year in which he struggled with his velocity after suffering from shoulder inflammation in June, and he has some of the nastiest stuff in the league.

If everything goes right? This is a juggernaut that cruises to a nine-, 10-game lead at the All-Star break, goes on to become the first 100-win team since the 2011 Phillies, wins the World Series and is one of the best all-around teams we’ve seen in years.

The Case Against

So what could go wrong in the Nationals’ plan for world domination? If closer Drew Storen’s postseason struggles carry over to the season, their bullpen will be in flux. Rendon’s left knee—his status for the April 6 opener is in question after he suffered an MCL sprain—could turn out to be a big problem, Harper’s injury issues could continue unabated and Wilson Ramos and Zimmerman have had trouble staying healthy, too. New second baseman Yunel Escobar could struggle in his first season in Washington. And with one or two injuries in the rotation, suddenly, the starting five isn’t exactly the Best Rotation in Baseball.

Red Sox, Mets, Cubs among potential playoff surprise teams for 2015

Expectations are so high that you wonder how Washington could possibly live up to them, as anything short of a World Series berth would be a huge disappointment for a team that hasn’t reached the NLCS in its only two postseason appearances. And yet, the Nationals, who have suffered two gut-wrenching NLDS losses the last three years, know as well as anyone else about the randomness of the postseason. A dominant regular season guarantees nothing in October. All it takes is an unlucky bounce, a bad managerial decision or a Madison Bumgarner-like performance from the other team, and there go Washington's dreams of an early November parade down Constitution Avenue.

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​​X-Factor: Casey Janssen

Longtime setup man Tyler Clippard has been one of the game’s best over the past few seasons, but Washington decided to sell high and dealt him to the Athletics after his second All-Star season. Enter Janssen, the former Blue Jays closer the Nationals believe can step into Clippard’s role. Janssen is coming off his worst season since 2009; he had a dominant first half but struggled down the stretch as his strikeout rate declined to 5.5 per nine innings for the season (he averaged 8.7 per nine from 2010 to '13). Nonetheless, Janssen got a one-year, $3.5 million deal from Washington over the winter and could be the key to a bullpen that is the team's weakness. If Storen struggles, Janssen becomes the most likely candidate to take over as closer.

Number To Know: 17.6

That was the WAR (according to FanGraphs) of the Nationals' starting rotation in 2014, which was second in baseball. And that was without Scherzer, who was the best pitcher on Detroit—the team with the top starting pitching WAR in '14. Expect a healthy Washington rotation to blow that 17.6 number out of the water.

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Scout's Take

Most Overrated: Drew Storen

“The one thing that scares me about this team? Storen at closer. I’m not ready to call him one of the top closers in the league, which some people think he is—it’ll be interesting to see how he bounces back from last October. We know about how long it took him to come back mentally from the blown save in the playoffs three years ago against the Cardinals. Well, now I wonder how he’s going to bounce back from his blown save [in Game 3 of last year’s NLDS]—if the Nationals don’t lose that game, I don’t think the Giants win that series.”

Most Underrated: Gio Gonzalez

“The guy who gets overshadowed is Gonzalez. They talk about the big three, but it wouldn’t shock me if Gonzalez has the best season of all of them. He is the No. 4 starter, but he could be a Cy Young contender. He may have the best curveball in the game, and after battling some arm problems, he and his curveball are all the way back. He looks great this spring, and I think he’s primed to have a big year.”