THE CONVENTIONAL wisdom says a team needs the benefit of good fortune to end up in its league championship series this time of year. But the paths of this year's National League playoff competitors suggest that the true necessity is a roster deep enough to overcome bad fortune. So before you chalk up the stomach-turning performance of the Phillies' starting pitching staff in 2013 to the loss of Roy Halladay, consider the following:

The Braves spent nearly the entire season without top-of-the-rotation starter Brandon Beachy and the last 2 months without Opening Day starter Tim Hudson. Neither was on the team's playoff roster.

The Reds lost Johnny Cueto (No. 4 in 2012 NL Cy Young voting) for the season after just 11 starts.

Wandy Rodriguez, the Pirates' No. 2 starter at the start of the season, was done after 12 starts.

The Cardinals lost top-of-the-rotation starter (and 2011 playoff ace) Chris Carpenter for the season in spring training.

The Dodgers spent most of the season, including the postseason, without Josh Beckett, Chad Billingsley and Ted Lilly.

In other words, each of the five National League teams that qualified for the 2013 postseason did so despite suffering one or more pitching injuries that, in totality, were the equivalent or near-equivalent of the Phillies' rotation losing Halladay.

So, how did those five teams survive? And what lessons might they impart on the Phillies as they attempt to avoid the rotational collapse that torpedoed their playoff hopes this season?

* Lesson No. 1: Have a major league-ready, blue-chip pitching prospect biding his time at Triple A at the start of the season.

For the Cardinals, that player was 22-year-old Shelby Miller, rated by Baseball America as the sixth-best prospect in the sport prior to the season (he was No. 8 pre-2012, No. 13 pre-2011 and No. 50 pre-2010). Miller ended up starting 31 games and had a 3.06 ERA, 8.8 K/9, 3.0 BB/9 and 1.0 HR/9.

For the Pirates, it was 22-year-old Gerrit Cole, who started 19 games with a 3.22 ERA, 7.7 K/9, 2.1 BB/9 and 0.5 HR/9. He entered the year at No. 7 on BA's Top 100 after ranking 12th before the 2012 season.

For the Braves, it was 22-year-old Julio Teheran, a Top 10 prospect in BA's Top 100 in 2011 and 2012 and No. 44 heading into 2013. His final numbers: 14-8, 3.20 ERA, 8.2 K/9, 2.2 BB/9, 1.1 HR/9 and more than six innings per start (30 starts).

The Reds didn't have a prospect on the level of Miller, Cole or Teheran, but they did have Tony Cingrani, who was ranked No. 82 by BA heading into the season. The 23-year-old contributed 18 starts and five relief appearances, posting a 2.92 ERA, 10.3 K/9, 3.7 BB/9 and 1.2 HR/9 to the cause.

Of the five NL playoff teams, only the Dodgers did not get a significant contribution from a starter who entered the season ranked in Baseball America's Top 100, and three of those were considered elite prospects. Unfortunately for the Phillies, their farm system is devoid of a major league-ready arm. Top prospect Jesse Biddle is much less polished than Miller, Cole, Teheran or Cingrani were at this time last year, while lefty Adam Morgan finished the season easing his way back from a shoulder injury. If healthy, a Cingrani-type season is a possibility.

* LessonNo. 2: Get good value on the free-agent market.

While the Dodgers' rotation did not get a significant contribution from the minor league system, they did get 30 starts and 192 innings from 26-year-old Hyun-jin Ryu, a Japanese import who they signed to a 6-year, $36 million deal. Without his 14-8 record and 3.00 ERA, they might not have qualified for the postseason. The Phillies will hope for a similar season from Cuban righty Miguel Alfredo Gonzalez.

The Pirates received a similar contribution from Francisco Liriano, who went 16-8 with a 3.02 ERA, 9.1 K/9, 3.5 BB/9 and 0.5 HR/9 in 26 starts after signing a 2-year, $7 million deal.

This year's market offers plenty of high-risk, high-reward candidates like Liriano: Phil Hughes, Scott Kazmir, Gavin Floyd and Edinson Volquez probably fit the mold closest, although there are bigger names available like Josh Johnson and Tim Lincecum. The trick is picking the right one.

* Lesson No. 3: Don't be afraid to experiment with wild cards.

Few would have predicted the seasons Jeff Locke and Charlie Morton turned in for the Pirates. The Braves threw 22-year-old Alex Wood into the fray for 11 starts and 20 relief appearances. Five different Cardinals aged 26 or younger started at least nine games. Again, the situation is a bit trickier for the Phillies given their lack of minor league starting pitching depth.

The Phillies' best hope is making a shrewd signing or two on the free-agent market. If they have the resources, it would be wise to err on the side of too many options, given the uncertainty surrounding Gonzalez and the struggles Kyle Kendrick endured over the last couple months. It would be a mistake to think that they only need to sign one starter given the apparent paucity of options in the minor league system. Keep in mind, the injury bug will not go on hiatus next season. The odds say the Phillies will have to deal with at least one significant loss from whatever their projected rotation is heading into spring training. In order to qualify for the postseason, they will need their staff to look like the aforementioned five in September as well as April.