Last January, the Reds made a bet on Sonny Gray that immediately paid off in a big way. In July, Cincinnati placed a similar bet on Trevor Bauer. This offseason, the Reds signed veteran left-hander Wade Miley to round out a rotation fronted by All-Star strikeout artist Luis Castillo.

The Cardinals can probably claim the National League Central’s most dominant starter: Jack Flaherty. The Cubs have the most name recognition with Yu Darvish, Jon Lester, Kyle Hendricks and José Quintana. The Brewers always seem to find a way to get the most out of their “out-getters.” And the Pirates believe their rotation is better than last year’s numbers might indicate.

But all of a sudden, the Reds have assembled a starting staff high on upside -- namely that of Castillo, Gray and Bauer -- with plenty of depth to spare. Here is a look at how the starting rotations currently stack up in the NL Central.

The best: Reds
The Reds already appeared to have a strong rotation of names going into the offseason, with a pair of 2019 All-Stars in Castillo and Gray along with Bauer and Anthony DeSclafani. Then they added to it by signing Miley to a two-year, $15 million contract in December.

As a rotation last season, Cincinnati was fifth in the NL in ERA and FIP and third in strikeouts and opponents’ batting average. The entire group, especially Gray, seemed to benefit from new pitching coach Derek Johnson and assistant pitching coach Caleb Cotham and their ability to both communicate easily while harnessing data to find ways to improve. Gray worked under Johnson while in college at Vanderbilt, and now Miley gets to reunite with his former pitching coach from Milwaukee.

Although the Reds’ rotation didn’t record a complete game last season, the pitching staff as a whole notched 10 shutouts -- the most for the club since 2012. Castillo is routinely heralded for having the best changeup in baseball -- a pitch Statcast showed him using 31.5% of the time -- while Gray and Bauer both have potent curveballs. Gray overcame a Spring Training right elbow injury and didn’t miss a start in the regular season. Over his final 16 starts, he was 8-3 with a 1.99 ERA and 13 quality starts. Perhaps the one question mark is Bauer, who is in his final year before free agency. While dealing with ankle and back injuries, he gave up a career-high 34 home runs with a 4.48 ERA. But he also turned in career highs in starts (34), innings (213) and strikeouts (253). DeSclafani showed improved consistency during his first fully healthy season since '15.

There is also depth with Tyler Mahle, Lucas Sims and top prospect Nick Lodolo if there is an issue or injury. Lodolo, the No. 48 overall prospect per MLB Pipeline, could be a candidate for a 2020 promotion despite being a first-round Draft pick just last year. In his first eight Minor League starts last summer, he notched 30 strikeouts and didn’t walk a batter. -- Mark Sheldon

The rest (in alphabetical order)

Brewers
Throughout David Stearns’ tenure atop the team’s baseball operations department, the Brewers have prioritized depth over investing in top-end starters, expecting to employ 8-10 “initial out-getters” throughout the course of the year.

This winter’s payroll shuffle meant the departure of Chase Anderson and Zach Davies via trade, replaced by former Padres Opening Day starter Eric Lauer and free-agent acquisitions Josh Lindblom and Brett Anderson. That trio joins two incumbents whom the Brewers believe have high ceilings: 2019 All-Star and presumptive '20 Opening Day starter Brandon Woodruff, and Adrian Houser. Both are entering their age-27 seasons.

Beyond that initial fivesome, the Brewers anticipate using Corbin Burnes and Freddy Peralta, two young pitchers who were part of last year’s early-season rotation before dropping out due to poor performance. Left-hander Brent Suter will begin the year in the bullpen, but he has the potential to make starts as well. The prospect closest to the Major Leagues is right-hander Trey Supak, who posted a 3.60 ERA over 152 2/3 innings in the Minors last season and was the Pitcher of the Year in the Double-A Southern League. Just like recent years, it will be a group effort in Milwaukee. -- Adam McCalvy

Cardinals
The Cardinals’ rotation, and specifically Flaherty’s second-half run, is a big reason why St. Louis won the division last season.

St. Louis’ rotation had a 3.15 ERA in the second half last year, second in the Majors to the Mets’ 3.13 mark. This season, they will return four starters: Flaherty, Dakota Hudson, Miles Mikolas and Adam Wainwright. The fifth spot will be up for grabs, with Carlos Martínez and Kwang-Hyun Kim, whom the Cardinals signed to a two-year deal this offseason, as the front-runners.

The health of Martínez’s shoulder will be the biggest unknown in his bid to return to the rotation, but if his shoulder can withstand the workload, the Cardinals could have another elite pitcher in their rotation. Kim, a left-hander, was signed as a starter out of the Korean Baseball Organization. He went 17-6 with a 2.51 ERA and 180 strikeouts over 190 1/3 innings in 31 games (30 starts) last year.

While the competition for the fifth starter seems to be between Martínez and Kim, the Cardinals will have around 12 pitchers come to Spring Training as starters. This includes John Gant and Ryan Helsley, two integral parts of the bullpen last year, and Daniel Ponce de Leon and lefty Austin Gomber. Jake Woodford, who was added to the 40-man roster this offseason, is on the cusp of the Majors as well. -- Anne Rogers

Cubs
The Cubs are banking on the idea that what they saw from Darvish in the second half last season is a sign of what's to come.

After an injury-marred Chicago debut in 2018, Darvish stumbled out of the gates in '19 before settling into an ace-like performance down the stretch. He posted a 2.76 ERA with 118 strikeouts and seven walks after the break, posting an MLB-record 16.86 strikeout-to-walk ratio for a second half (min. 50 innings). In one incredible streak between July and August, Darvish had 44 strikeouts and zero walks in a stretch of five starts. That is the No. 1 arm Chicago needs for a rotation that isn't getting any younger.

Hendricks is a steady force in the rotation, and he will be joined by Lester and Quintana on the staff. Right now, Tyler Chatwood projects to be the top candidate for the fifth spot after a solid 2019 as a swing man. A vacancy was created when Cole Hamels left via free agency and signed a one-year deal with the Braves. Prospects Adbert Alzolay and Alec Mills could also contend for the No. 5 spot, with Colin Rea, Jharel Cotton and Tyson Miller offering depth options.

Last year, Chicago's starters combined for 888 innings (tied for fourth most in the National League) and turned in a 4.18 ERA (3.74 ERA at home vs. 4.65 ERA on the road). The rotation's 15.7 WAR (via FanGraphs) ranked fourth in the NL. -- Jordan Bastian

Pirates
Last spring, the Pirates thought their rotation would be the solid foundation of a surprisingly successful team. Instead, their rotation was the surprising weakness of a 93-loss team. Injuries piled up, and starters struggled to perform up to their expectations. But the Bucs believe their rotation can be better this year, despite a lack of meaningful offseason upgrades, because they see individual room for improvement in all six of their top starting options.

Joe Musgrove returns as the only starter who went wire to wire without hitting the injured list last season. Chris Archer, who’s bound to be a trade candidate by the Deadline, is hoping for better results after a disappointing start to his tenure in Pittsburgh. Trevor Williams expects he’ll return to form with better health and a more repeatable delivery. Top prospect Mitch Keller flashed his top-of-the-rotation stuff amid bad luck and early jitters. Steven Brault showed signs of promise in the second half, and Chad Kuhl is coming back from Tommy John surgery hoping to harness his high-octane arsenal.

There’s not an “ace” in the group, at least not with Jameson Taillon out for the year following Tommy John surgery. But if they all live up to their potential, they’re good enough to keep the Pirates in every game they play -- especially if they benefit from better defense behind the plate and in the field.

The Pirates have six options for five spots and, thus, some form of spring competition brewing. They’ll also have veteran left-hander Derek Holland in camp on a Minor League deal with a chance to earn a rotation spot. They’ll have Triple-A depth to start the year in the form of right-handers JT Brubaker, Cody Ponce, James Marvel and Héctor Noesi. Prospect Cody Bolton has a chance to reach Triple-A later this year. And the Pirates have some fascinating high-ceiling pitching prospects in the lower Minors -- namely first-round Draft pick Quinn Priester, recently acquired right-hander Brennan Malone and promising righty Tahnaj Thomas. -- Adam Berry