Each week I'll answer a handful of the most pertinent questions I've received during the week in my attempt, weak as it might be, to bring insightful fantasy analysis to the fore (my email address is listed at the bottom of the piece if you wish to drop me a line).

I'm in a keeper league with no salary concerns. Who would you keep next season, Chris Carpenter or Matt Cain? -- Evan, Exeter, N.H.

Five months ago this would have been a landslide in favor of the younger, healthy Cain, but now you have to go with Carpenter even with all the health concerns, don't you? Let's compare the two in a variety of categories.

Cain: 12-4, 2.27 ERA Carpenter: 12-3, 2.27 ERA

Pretty much identical there.

Cain: 1.17 WHIP, 7.20 K/9, 2.21 K/BB Carpenter: 0.98 WHIP, 6.68 K/9, 5.10 K/BB

Carpenter surges ahead here thanks in no small part to his substantial ability to throw strikes with a sterling BB/9 mark of 1.31 compared to Cain's 3.25 mark.

There is also history to consider, on both sides.

The negative with Carpenter is that he has been injured off and on for years. When he is healthy, as he is now, there are few who are better. However, you can't simply forget that he made just five appearances the past two seasons.

As for Cain, he is still young at just 24 years old, and is well on his way to a fourth straight season of 190-innings. Regardless, his success this season is has been surprising given that the majority of his numbers, other than his ERA and record, are nearly identical to his career work.

2009: 7.20 K/9, 3.25 BB/9, 2.21 K/BB, 0.93 HR/9, 1.17 WHIP Career: 7.58 K/9, 3.69 BB/9, 2.05 K/BB, 0.79 HR/9, 1.26 WHIP

What that means is that Cain can rightly be said to be have been lucky this season. How lucky? Though his line drive rate is 18.2 percent, just below his 18.6 career mark, his BABUP has dipped .019 points to .258. In addition, his left on base percentage is almost 87 percent as of this writing, this after three years of marks between 69.8 and 75.3 percent.

Bottom line is that when right, this really isn't a viable matchup as Carpenter is clearly the better hurler. Cain is young and has not a whiff of injury history to be concerned with; but in my mind you keep talent, and Carpenter has that category locked up.

What in gods name has happened to Carlos Pena? The homers are nice but I didn't think I was getting the next Rob Deer when I drafted him this year. -- Nick, New Mexico

Carlos Pena leads the American League with 31 home runs, his third straight campaign with the many. With 77 RBI he is also 23 away from a third straight triple-digit effort. Pena has also scored 73 runs, just three less than the 76 he posted last season, and with two steals he has matched his total from the last two seasons. One last thing, his OPS of .865 is nearly a match for his .871 mark from last season.

So what is the issue with Pena? It's that batting average which is currently at a Rob Deer-like .216 (Deer hit .220 in his career). First things first, Pena's .282 average in 2007 was a fluke. Besides sporting a mere .246 average in his career, Pena has never hit over .250 in a season of at least 100 at-bats other than that '07 campaign. Think about that -- he has only one season of hitting above .250 in his career so it's not like he has ever been a boon in that category. Still, his current struggles are still a bit unexpected. Two main reasons for his struggles are a line drive rate of 16 percent, the lowest mark of his career (18.4 percent), and a BABIP mark of .243, a full .050 points below his career mark (it hasn't been below .288 in any season). If the line-drive rate and the BABIP rebound moving forward, and history tells us they should at least somewhat, we could see Pena's average return to a more respectable level for him, though that level is still decidedly sub par.

Can Edwin Jackson hold on the rest of the way? I'm loving my 22nd round pick who continues to impress. -- Jim, Santa Monica, Calif.

I was worried about Jackson myself so I checked into his work earlier this week in Twists and Turns. What I pointed out in that article is that Jackson has been throwing a lot of pitches lately, and here are the two main numbers: 114 pitches per game over his last seven starts and 112 pitches over his last three starts despite an average of only 5.1 innings in that time. Jackson is also only 31.2 innings short of his career-high with a quarter of the season remaining, so there is always the concern of how a guy will handle his first 200 inning season. Is he starting to wear down?

As for his performance, it has been spectacular. Just look at a comparison of his work this season versus his career prior to this point.

2009: 2.79 ERA, 1.09 WHIP, 7.12 K/9, 2.45 K/BB Career: 5.15 ERA, 1.63 WHIP, 6.14 K/9, 1.36 K/BB

That isn't just a little improvement, that is massive improvement for the Tigers' hurler. In fact, a bit too much for my taste. When you add in the innings concerns, the fact that he is throwing a lot of pitches, and the fact that over his last five starts he has a 3.90 ERA, 1.57 WHIP and a 1.64 K/BB mark, I think it would be wise to expect Jackson to fail to live up to his early season success. I'm not predicting a meltdown, but I would be shocked if he didn't finish with an ERA over 3.00 and a WHIP over 1.20 by the time the season is complete.

I'm flustered. I waited for weeks for Ian Snell to be recalled to the bigs as he was dominating in the minors, and when he was moved to the Mariners I thought my patience would be rewarded. Now, he looks worse than ever. What gives? -- Ryan, New York

You aren't alone, Ryan.

Snell was awful in Pittsburgh going 2-8 with a 5.36 ERA and 1.62 WHIP in his 15 starts before he was banished to the minors to find himself, and oh did things click. Snell had that 17 K effort and thoroughly dominated Triple-A batter to the tune of a 0.96 ERA, a 1.10 WHIP, an 11.33 K/9 mark and a 3.62 K/BB mark. Obviously, hopes were extremely high after that work, and the move to the Mariners also seemed to signal both a fresh start and the chance to pitch for a team that plays its home games at a yard that favors pitching.

Snell looked strong in his first start against the Rangers, in Texas mind you, allowed just two runs over six innings sending everyone scurrying to the waiver-wire. Alas, Mr. Hyde appeared the past two outings as Snell was bombed while at the same time being completely unable to locate the strike zone. Hide the women and children before you read on: in 7.1 innings he allowed 11 hits, 11 runs and walked nine batters. Ghastly. As a result, he has been worse in his three starts with the Mariners (8.78 ERA, 1.95 WHIP) than he was with the Pirates. Snell might one day pan out, but given his complete inability to throw strikes or to get major league batters out with any frequency do yourself a favor and remember this adage -- late in a year there is nothing more destructive to a team than a major flameout on the hill. Let someone else worry about this headache.

Can Neftali Perez throw enough innings to make a difference to my fantasy squad in a standard 12-team league? -- Johnny, Tacoma, Wash.

Well Johnny, I can't really answer that question without knowing more details about your team and league, but I'll still offer a few thoughts.

Feliz has been amazing in his limited work recording outs via the strikeout 65% of the time in his 6.2 innings. As amazing, he hasn't walked a single batter in his 6.2 inning while allowing just one hit. Of course, when your "changeup" is 90 mph, yes his changeup, and your fastball comes in at 99 mph, you can understand why hitters who have never seen him before are doing a lot of swing and missing.

Can he make a difference the rest of the way? Let's play a game of what if. The Rangers have 49 games left. Let's say that over that time that Feliz throws 25 innings. We can't posit that he will continue along the lines he has flashed to start his career, but let's say he posts a 3.00 ERA, 1.00 WHIP and 12.0 K/9 the rest of the way. Well that ERA and WHIP are akin to the work that Cliff Lee has given the Phillies in his three starts with the club, and that is some seriously solid pitching. Still, 25 innings really isn't enough to make a big dent, but it would be enough, at that level, to likely drop your ratios enough to gain a point in each category. Throw in 30 Ks, more than enough to also move you up a spot in the standings, and you have to say that his potential outlay, while not likely to rise to the level of real prominence, certainly could be enough to gain you those extra few spots in the standings to make a difference.

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