Deep impact: 5 teams with most rotation depth

Dodgers, Red Sox equipped with 10-plus starters

Deep impact: 5 teams with most rotation depth

With the American League pennant up for grabs, the Indians turned to a left-hander who had served as a key piece of the starting rotation almost all season -- with the Triple-A Columbus Clippers.

The pitcher was 24-year-old Ryan Merritt in Game 5 of the AL Championship Series at Rogers Centre, with Cleveland trying to advance past a Toronto club stacked with dangerous bats. A former 16th-round pick, he had made his first and only other Major League start about three weeks earlier.

If ever there were an advertisement for the importance of rotation depth, this was it. With Carlos Carrasco, Danny Salazar and Trevor Bauer injured, Merritt delivered, tossing 4 1/3 scoreless innings before handing the reins to Cleveland's bullpen in a 3-0 victory.

Merritt's scoreless start

That situation was an extraordinary one. But it also drove home the point -- as cliched as it may be -- that a team can never have too much starting pitching.

Research conducted by MLB.com a year ago showed that since MLB expanded to 30 clubs in 1998, the average team used 10.3 starters in a season. During that time, 136 teams had no more than one pitcher make 30-plus starts, while only six got at least that many from each of their top five. Meanwhile, the 40 clubs that qualified for the postseason from '12-15 called on a starter outside their pre-Spring Training projected rotation an average of 39 times.

With those numbers in mind, and with teams about to report to camp, here is a look back at how rotation depth factored into the 2016 season and how it's shaping up for '17.

Looking back
Last season marked the fourth in a row in which no team got through 162 games using six or fewer starters. Only the postseason-bound Blue Jays went with seven, and on the other end of the spectrum, the rebuilding Braves trotted out 16 pitchers. Overall, big league clubs averaged 11.1.

For a starter, 30 outings is close to a full season of work. No team in 2016 got five pitchers to that mark, and as many finished the year with no 30-start pitchers (Padres, Pirates) as finished it with a quartet (Cardinals, Cubs). The plurality of clubs (11) had only a single hurler make it to 30, including the AL champion Indians and the Dodgers, who came up two wins shy of meeting Cleveland in the World Series.

The 30 Major League teams used an average of about 11 different starting pitchers last season.

While the number of starters used tells part of the story, it's also revealing to examine the load those arms carried.

Setting aside each team's top-five pitchers in terms of starts, the average club turned to a "depth" starter 35.6 times in 2016. The totals ranged from just 10 apiece for the Blue Jays and Cubs to a whopping 68 for the 94-loss Padres, who had only two pitchers make more than 18 starts. Not surprisingly, postseason teams (28.2) didn't lean as much on those non-top-five starters than those clubs that didn't qualify (39.3).

Of course, plans can change considerably between February and October, as injuries strike, trades materialize, big leaguers underperform and prospects force their way to the Majors. In other words, the workload for the "depth" starters increases based upon clubs' projected rotations at the end of the offseason. Looking just at the 10 postseason clubs from last year, they needed an average of 33 starts from pitchers who were outside their top fives when camp began.

MLB Central on Dodgers' rotation

On one end of the spectrum, the Blue Jays and Cubs barely needed to dig into their depth. Teams such as the Indians and Nationals used fewer than 25 starts apiece from those outside their projected top five, but they entered the postseason at less than full strength due to injuries to pitchers like Carrasco and Stephen Strasburg. Then there were the Dodgers, who won 91 games despite using a non-projected starter for 70 out of 162 games. Only Kenta Maeda made more than 26 starts for L.A.; Clayton Kershaw made just 21, and injuries limited the trio of Brandon McCarthy, Brett Anderson and Hyun-Jin Ryu to a combined 13.

Of course, rotation instability played a major role in the seasons of many non-postseason clubs as well. Take the disappointing 78-83 Pirates, who used 14 starters (six of them rookies), none taking the ball more than 21 times. Or consider the injury-riddled 74-88 Angels, who entered the spring with eight viable starters but then saw them make fewer than 14 starts apiece on average, as C.J. Wilson spent the whole year on the disabled list and three others sustained elbow injuries.

Looking ahead
A handful of free-agent pitchers remain available, such as Doug Fister, Colby Lewis and Jered Weaver. But with most clubs knowing what starters they are bringing to camp, here is a look at five that might have the depth to weather some storms in 2017.

Dodgers: L.A. has emphasized building depth under Andrew Friedman and Co., while also taking chances on some injury-prone pitchers. The club brought back Rich Hill this offseason, but it certainly isn't counting on him for 30-plus starts. A rotation of Kershaw, Hill, Maeda, Scott Kazmir and 20-year-old phenom Julio Urias would still leave the likes of McCarthy, Ryu, Alex Wood, Ross Stripling and rookie Brock Stewart in reserve, if healthy.

Red Sox: The splashy acquisition of Chris Sale gives Boston a three-headed monster, with David Price and reigning AL Cy Young Award winner Rick Porcello. But even after trading Clay Buchholz, the club still has three strong starters for two spots in Drew Pomeranz, Eduardo Rodriguez and Steven Wright. Roenis Elias spent much of last year at Triple-A Pawtucket, but he was a useful starter for Seattle from 2014-15, and fellow southpaws Brian Johnson and Henry Owens provide further Minor League backup.

Mets: Their rotation has as much variability as anyone's, depending on health. Last year, the group dealt with a rash of injuries, but the quartet of Noah SyndergaardMatt HarveyJacob deGrom and Steven Matz has obvious upside. Bartolo Colon's rubber arm is no longer around as insurance, but unheralded rookies Robert Gsellman and Seth Lugo both pitched well when pressed into duty in 2016. The wild card is Zack Wheeler, who hasn't pitched since '14 but has a 3.50 career ERA.

MLB Now: Mets 2017 rotation

Cardinals: The steady Lance Lynn missed all of 2016, but he is now 15 months removed from Tommy John surgery and has been going through a normal offseason throwing program. Top prospect Alex Reyes authored a stellar 46-inning debut late last season, and he looks to be big league ready. Combine Lynn and Reyes with Carlos Martinez, Mike Leake, Adam Wainwright and Michael Wacha, and that's six good options. Rookie Luke Weaver also debuted in '16, leading the pack of further depth options.

Cubs: Chicago, which let Jason Hammel go this offseason, is unlikely to keep its rotation as healthy as it did last year. But the club has made some intriguing moves of late to protect itself. Anderson, signed as a free agent, has dealt with a plethora of injuries, but he has been solid when healthy and should challenge Mike Montgomery for the fifth spot. Trade acquisition Eddie Butler is a former prospect who might benefit from escaping Colorado and working with Cubs coaches. Casey Kelly (Minor League deal) is another ex-prospect who fell on hard times, and Rob Zastryzny had a successful cup of coffee in 2016 (mostly in relief).

Andrew Simon is a research analyst for MLB.com. Follow him on Twitter @AndrewSimonMLB. This story was not subject to the approval of Major League Baseball or its clubs.