A few spring training storylines to watch

The countdown is on, with Nationals pitchers and catchers reporting to Space Coast Stadium in Viera, Fla., on Thursday. So here are a few storylines to watch throughout spring training:

* Can Tanner Roark re-establish himself as a permanent member of the Nationals starting rotation? Many pitchers would have thrown a fit or even demanded a trade after being bumped from the rotation to the bullpen following a 15-win campaign with a sub-3.00 ERA. Though Roark handled the demotion with professionalism, his game suffered on the field.

Roark posted a 3.74 ERA in 28 relief appearances, but that number inflated to 4.82 in his 12 starts sprinkled throughout the season. The 29-year-old showed better consistency after rejoining the rotation in September, allowing five runs over 17 2/3 innings in his final three starts of the season.

When asked in December if Roark would be part of the starting rotation in 2016, new Nationals pitching coach Mike Maddux responded "It's his job to lose."

Veteran right-hander Bronson Arroyo could challenge Roark. Arroyo, who turns 39 on Feb. 24, hasn't pitched professionally since undergoing Tommy John surgery while with the Diamondbacks in July 2014. But if Arroyo impresses in Viera, it could leave new Nationals manager Dusty Baker with an interesting decision. Arroyo was part of Baker's rotation in Cincinnati from 2008-2013, going 82-68 with a 4.17 ERA in 196 starts over the stretch.

* Will Wilson Ramos finish the season as the Nationals' starting catcher? At 28, Ramos is entering the final year of his contract. After battling numerous injuries, Ramos remained healthy in 2015, appearing in a career-high 128 games. He was a Gold Glove finalist and caught both of Max Scherzer's no-hitters. But Ramos struggled mightily at the plate, striking out 101 times with 16 double plays in 504 plate appearances while posting a career-worst .229/.258/.358 slash line.

The Nationals were reportedly having trade talks regarding catchers this winter. Brewers catcher Jonathan Lucroy, who finished fourth in the National League Most Valuable Player vote in 2014, was linked briefly after indicating he would welcome a move to a contender.

* Who will start at shortstop on opening day? Danny Espinosa is the favorite to be the Nats' everyday shortstop after waiting behind Ian Desmond for the past five-plus seasons. After a few tough offensive seasons, the gritty Espinosa regained some confidence at the plate, slashing .240/.311/.409 with 13 homers, 21 doubles, one triple and 37 RBIs in 412 plate appearances.

Veteran infielder Stephen Drew, signed this winter, will battle Espinosa. Drew has combined to hit just .185 the last two seasons but he did smack 17 homers in 2015.

And all eyes will be on 22-year-old Trea Turner this spring. Turner is ranked among baseball's top prospects and is expected to be the Nationals' shortstop of the future. He slashed .225/.295/.325 in 44 plate appearances after making his major league debut late last August. Most expect Turner to begin the season in the minors, but a stellar Grapefruit League season may force the issue.