No, David Herndon isn’t one of the main reasons the Phillies have disappointed thus far in 2010.

Not even close.

Obviously he doesn’t deserve the same amount of heat that teammates like Shane Victorino and Brad Lidge have been getting. But that doesn’t mean Herndon should be getting a free pass.

It’s safe to say that Herndon, the 24-year-old rookie sinker-baller, hasn’t exactly been a positive addition to the bullpen this season.

Not just because opponents are hitting a ridiculous .343 against him. Not just because he’s allowed nine out of his 14 inherited base runners to score since May 14.

But also because he is in part preventing the Phillies from giving some of their minor league prospects a shot in the majors. Herndon has hand-tied the Phillies.

How? Well, entering 2010, Herndon was out of options.

In other words, the Phillies could not send him to the minor leagues. They’d have to keep him on their 25-man roster all season (barring injury, of course) or be forced to offer him back to his former club, the Los Angeles Angels.

With the Angels’ Double-A affiliate last year, Herndon had a 3.03 ERA and a 1.29 WHIP in 50 games.

The young righty impressed the Phillies in Spring Training this season with a 1.42 ERA in 10 games. But he hasn’t been anywhere near as effective with the big club in 2010, despite pitching in 32 games so far.

It’s hard to imagine Herndon would have remained on the Phillies staff this long if he actually had minor-league options. The thing is, the Phillies have some fairly decent arms at Double and Triple-A that could have replaced Herndon already in the pen.

How about Drew Carpenter? The 25-year-old righty has been biding his time at Triple-A since 2008 and has amassed an 18-14 record and a 3.43 ERA overall with Lehigh Valley.

How about Vance Worley? The 22-year-old right-hander was 9-4 with a 3.03 ERA in the minors this season before pitching in one game for the big club on July 24.

OK. Both Carpenter and Worley are starting pitchers, so maybe the Phillies wouldn’t want to use them in the Citizens Bank Park bullpen.

But what about Scott Mathieson? He’s been the Phillies’ best “feel good” story since 33-year-old rookie Chris Coste made his major-league debut in 2006.

Mathieson made eight starts for the Phils four seasons ago before suffering through a string of severe injuries, including one that required Tommy John Surgery at the end of ’06.

It’s taken the 26-year-old Mathieson a long time to rise back through the minor leagues, but he’s now having a fantastic season as the IronPigs’ closer, posting a 2.85 ERA and 20 saves. He’s allowed only 34 hits in 47 innings, striking out 61 while walking just 17.

Mathieson, like Worley, has pitched in just one major-league game so far in 2010.

What about journeyman Nelson Figueroa? He actually did better than Herndon when given a chance with the Phillies this year, posting a 3.46 ERA and a .220 opponent batting average in 13 games.

Houston claimed Nelson off waivers once the Phillies designated him for assignment July 15.

Of course, there’s no guarantee any of those guys would have pitched much better than Herndon has. They might have been even worse. But we don’t know. And one of the main reasons we don’t know about any of them is because Herndon has been occupying a spot in the bullpen all season.

The Phillies like Herndon’s ability as a sinker-baller, but so far in 2010 the righthander has proven to be nothing more than a useful arm in “mop-up duty”—slightly more effective than Danys Baez.

Offering David Herndon back to the Angels might not be such a horrible thing. He hasn’t made the most of his generous four-month opportunity with the Phillies in the bigs, so it’s time to see if any of the Phils’ minor-league hurlers can do any better.

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