By the Numbers: Studying Strand Rates

There are a lot of ways to find pitchers who will be bargains or busts on Draft Day. An up and coming player looks ready for a breakout ... bargain! A veteran has been living off his reputation for one season too many ... bust! We can spot trends in a pitcher's performance that lead us to think he is overrated or underrated. But how can we tell if a pitcher's performance is being propped up -- or held back -- by his bullpen?

Note: The Strand Rate metric used was developed by Ron Shandler. He also performed the research that established the normal rates and the patterns of variation.

Lucky for us, a statistic called Strand Rate can help us track the degree to which a pitcher is supported by his bullpen. Strand Rate is the percentage of baserunners that reach by hits (excluding home runs) and walks that do not go on to score earned runs. A normal strand rate is around 70%, so on average, seven out of every 10 runners reaching base by hit or walk don't make it home. This rate is a product of a pitcher's ability to keep his baserunners from scoring, but it also results from relievers' ability to keep inherited runs from scoring.

Strand Rate gives us a different way to spot bargains and busts. If a starter has a rate well above 70%, there is an excellent chance that his ERA is getting a lot of help from relievers who clean up his messes. A rate well below 70% is a good sign that an incompetent 'pen is inflating his ERA. Pitchers in these situations will see changes in their ERA, and ultimately wins, if the quality of their support changes.

A pair of Reds hurlers, Bronson Arroyo and Matt Belisle, provide a good example of how similarly skilled pitchers can wind up with different ERAs due to Strand Rate. Both Arroyo and Belisle posted nearly identical WHIPs and home run rates in 2007. Yet despite allowing baserunners and dingers at a similar rate, Belisle's ERA was more than a run higher. Belisle is certainly responsible for letting some of his own runners score, but he was also a victim of the Reds' notoriously leaky bullpen, which compiled an NL-worst 5.10 ERA.

Player Wins ERA WHIP HR/9 Strand %
Bronson Arroyo 9 4.23 1.40 1.2 73 %
Matt Belisle 8 5.32 1.44 1.3 66 %

So does this mean that Belisle is a bargain in 2008? It depends on whether his bullpen will improve over last year. We'll check back on this later.

We can use the same technique to identify potential busts. For example, the Braves' bullpen was clearly helpful to two of their top starters, John Smoltz and Chuck James. While few would dispute that Smoltz is a very useful Fantasy pitcher, can he compile 14 wins and an ERA close to 3.00 again without help from the likes of Rafael Soriano and Peter Moylan? Can Chuck James be counted on for double-digit wins when he coughs up nearly two home runs every nine innings? Those stratospheric Strand Rates could be a signal to proceed with caution ... but we will check on this later, too.

Player Wins ERA WHIP HR/9 Strand %
John Smoltz 14 3.11 1.18 0.8 76 %
Chuck James 11 4.24 1.38 1.8 77 %

With less than three weeks to go until opening day, it appears that most teams have done little to change the makeup of their bullpens. However, a few clubs appear primed for relief upgrades and downgrades this season. Taking a peek at the changes to these bullpens, we can add some names to our bargain and bust lists.

Bargains from Bullpen Upgrades

Cincinnati: The suspense is over. Pencil in Belisle as a bargain candidate, because Francisco Cordero is a major upgrade at the back end of the bullpen. Also, Todd Coffey and Mike Stanton are due for bounceback years, as last year’s ERAs and WHIPs were exaggerated by H/BIPs over 35%.

Tampa Bay: Andy Sonnanstine (58% Strand, 33% H/BIP) and Edwin Jackson (68%, 35%) were both victimized by the worst bullpen in baseball last year and by bad luck, so this year they will be bargains. The additions of Troy Percival and Trever Miller to the Rays' pen, along with a full year of Dan Wheeler, will provide better support than the 100-plus innings they got from Brian Stokes and Shawn Camp in '07.

Chicago White Sox: In 2007, Jose Contreras had his worst season on the South Side. His 65% Strand Rate shows that he bore the brunt of his bullpen's struggles, and his unlucky 34% H/BIP did him no favors either. Random chance should take care of his high H/BIP, which will lower his WHIP. Adding Octavio Dotel and Scott Linebrink to the bullpen in place Ryan Bukvich and David Aardsma should help Contreras' Strand Rate and ERA.

Philadelphia: What do you get when take rebound seasons by Clay Condrey (33% H/BIP in 2007) and Francisco Rosario (40%) and add Brad Lidge as your closer? A better Phillies bullpen and good news for J.D. Durbin. His 65% Strand Rate from last year should go up, so ERA and wins should improve as well in 2008. The catch here is that he may not win a spot in the rotation. However, if he snags the fifth starter's role, he is worth a flyer, despite what last season's stats suggest.

Busts from Bullpen Downgrades

Milwaukee: The Brewers lost Cordero to the Reds and Matt Wise to the Mets and have replaced them with Eric Gagne and David Riske (he of the 86% Strand Rate and 27% H/BIP in 2007 -- a classic relief bust candidate). Salomon Torres and Guillermo Mota could help matters with comeback seasons, but either way this is a bullpen in decline. That means Ben Sheets is unlikely to repeat his 73% Strand Rate from last year, and his ERA could climb. Should Carlos Villanueva grab a rotation spot, he will fall even harder, as indicated by last season's 75% Strand Rate and 27% H/BIP.

Seattle: Miguel Batista won't likely achieve another 73% Strand Rate, so be prepared for an ERA close to 5.00. This is what happens when George Sherrill leaves town and you leave it to Sean White or R.A. Dickey to soak up those innings. Yes, J.J. Putz will continue to be a good closer, but he will cease to be the luckiest man on Earth (20% H/BIP in 2007).

Pittsburgh: Tom Gorzelanny and Ian Snell gave Pirate fans some hope for the future when they compiled sub-4.00 ERAs as the staff's aces. That hope may be short-lived, because those ERAs were the product of some bullpen help. Shawn Chacon's 76 innings of relief work will be missed, as will Damaso Marte's over-his-head 2.38 ERA. Gorzellany and Snell are good bets to see their ERAs head north of 4.00.

These five starters all accumulated high Strand Rates in 2007, just like Smoltz and James. As long as they are wearing the Braves uniform, we can expect them to repeat their performances from last year. Soriano and Moylan are returning, and Tyler Yates (64% Strand Rate, 32% H/BIP in '07) should be much better. We can close out our list of potential busts and leave the names of Smoltz and James off of it.

Al Melchior was recently a Fantasy columnist and data analyst for Baseball HQ and will be providing advice columns for Click here to send him a question. Please put "Melchior" in the subject field.

Data Analyst

Al Melchior has been playing Fantasy Baseball since 1994, getting his start in the Southern Maryland Anthropomorphic Baseball League (SMABL). He has been writing about Fantasy Baseball since 2000, getting... Full Bio

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