ST. LOUIS -- The Cardinals largely surpassed expectations this year with a second-half turnaround that led them to a National League Central title and a spot in the NL Championship Series. But their season ended quickly and painfully with a four-game sweep by the Nationals.

The good news is that last season was an improvement from the previous three, and the Cardinals can build on their successes for 2020. To do that, though, there are some issues they need to address. Here are five questions facing the Cardinals this offseason.

1. Will they offer a long-term contract to Ozuna?
The Cardinals haven’t publicly discussed offering free-agent Marcell Ozuna a long-term contract, even though he said he’d like to stay in St. Louis. The first step would be to extend him a qualifying offer, which is a one-year deal valued at $17.8 million. If he declined it, he could negotiate a new deal with the Cardinals or seek a new team that would be willing to give up a Draft pick to sign him.

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Ozuna showed flashes of the cleanup hitter that the Cardinals wanted him to be this year. He hit 29 homers with 89 RBIs, even though he spent five weeks on the injured list. But in September, he was 15-for-100 (.150). He erupted in the NLDS (9-for-21), but cooled off in the NLCS (3-for-16). He also had some costly defensive misplays.

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The Cardinals need a consistent cleanup hitter behind Paul Goldschmidt. Ozuna showed he could fulfill that role, but his streakiness might mean that the Cardinals will look elsewhere.

2. How can the offense become more consistent?
St. Louis’ struggles in the NLCS were not limited just to Ozuna. The Cardinals struck out 48 times in four games against a star-studded Nationals rotation. They scored just six runs -- and four of those came in Game 4, after falling behind by seven in the first inning. The series exposed the weak spot of this St. Louis team: An inconsistent offense.

Goldschmidt led the club with 34 homers (tied for 29th in the Majors) and 97 RBIs (tied for 25th). The three-four punch of Goldschmidt and Ozuna in the middle of the lineup carried the Cards through the NLDS but disappeared in the NLCS. Whether Ozuna stays or goes, St. Louis will have to address its offensive struggles and figure out a way for the lineup to click more than it did last season.

3. What will the 2020 rotation look like?
Jack Flaherty, Dakota Hudson and Miles Mikolas will be back as starters in '20, barring injury. Adam Wainwright and Michael Wacha are free agents. Wainwright hasn’t announced yet whether he’ll return or retire. If he returns, it’s likely that the Cardinals will offer him a one-year contract like they did for '19. It’s unlikely that the Cardinals will give a qualifying offer to Wacha, and that will open a spot for another available starter on the free-agent market or an in-house candidate.

Daniel Ponce de Leon has been on the cusp of the rotation, and he impressed as a long-inning reliever when he got the chance late in the season. Left-hander Austin Gomber lost most of 2019 to injury, but he could compete for a starting spot in 2020. There is the possibility of Alex Reyes’ return, too.

The Cardinals are also open to Carlos Martínez, who took over as closer this year after Jordan Hicks had season-ending Tommy John surgery, getting back on a starter's workload this winter and competing for a spot in the rotation in Spring Training. That will require Martínez to stay healthy, and lingering weakness in his right shoulder caused him to stop his throwing program last spring and saw him moved to the bullpen in '19.

If Martínez does end up in the rotation, the Cards will have to find a reliever to take over as closer before Hicks’ return, which is likely to be midseason.

4. Who’s in the outfield?
Among the current outfielders and prospects who might be with the club next year, the Cardinals have eight players for three starting spots: Ozuna, Dexter Fowler, Harrison Bader, José Martínez, Lane Thomas, Randy Arozarena (St. Louis’ No. 10 prospect, per MLB Pipeline), Tyler O’Neill and Dylan Carlson (St. Louis’ No. 1 prospect and No. 24 overall). Tommy Edman and Yairo Muñoz also could slot into the outfield at some point.

In center, Bader excels on defense but he slashed just .205/.314/.366 and his offensive struggles became so illuminated that he was demoted to the Minors. Thomas could compete with Bader for the starting job. He only got 38 at-bats last season and was sidelined with a right wrist fracture at the end of the year, but he hit .316 and showed solid defense. Arozarena didn’t get many chances with the Cards this year, but he was included on the club's postseason roster. He could join Martínez as a bench option and extra outfielder next year.

The Cardinals also want to give the switch-hitting Carlson a shot at making the roster at some point next season, whether that’s by Opening Day or later. While Carlson is projected to be a corner outfielder in his career, the Cards ensured that he saw time in center in the Minors last year. He will compete with Bader, Thomas and Arozerena for that center spot.

Fowler has two years left on his contract and showed flashes of the leadoff hitter the Cardinals wanted him to be when they signed him. But he also disappeared in the playoffs, which didn’t help the Cardinals overcome their offensive issues. He’ll likely show up in right or center next year.

Left field is up for grabs if Ozuna leaves. O’Neill -- if he’s healthy -- is an in-house candidate to take over. It could also be a spot for Edman if he doesn’t fit in the infield. Or it could be a spot that the Cardinals fill externally, as a way to add a big bat to the lineup.

5. How about third base?
Third base is the one infield spot in the starting lineup that’s a little uncertain, barring injury. Will Matt Carpenter bounce back, or will Edman take over, as he did in the second half? The Cardinals will want to find a regular spot for Edman, but that could be in the outfield. They probably don’t want Carpenter on the bench, considering that he signed a two-year, $39 million deal for 2020-21 with an $18.5 million vesting option for '22.

Carpenter provides a strong left-handed bat when he’s on, but when he’s not, it only feeds the inconsistent offense. Edman provides versatility throughout the lineup and on the field. But with a surplus in the outfield, the Cardinals will have to figure out how Edman fits in.