All current indications seem to point to the Mariner lineup staying nearly static from the past year with a lone exception. This is going to be a rudimentary, quick peek into what we might expect from that one change.

In 2007, Jose Guillen batted .290/.353/.460. He was pretty lucky to have done so, with a higher than expected BABIP, but that’s tangential to our intended discussion here since Jose Guillen’s 2008 performance is not what we are concerned with. According to The Hardball Time, Guillen played 1273 innings and snagged 234 of 273 balls in zone and 34 out of zone. Taking the league rates for rightfielders, the average rightfielder would have gotten to 237.5 balls in zone and 47.5 out of zone. Adding these up and you get that Guillen made 17 fewer plays than our expected average defender over the course of 1273 innings.

With the performance in 2007 established, we move on to the more difficult part; projecting our 2008 performance. This is going to come primarily from Adam Jones. Jones is the subject of a few favorable projections already, notably ZiPS which pegs him as a .276/.335/.477 hitter next year. While I am sure that seems tad optimistic, let us not dismiss it outright, but instead delve a little deeper and see where we feel afterwards. Jones is not the easiest projection since he has such a limited big league sample to draw from. Luckily, I prefaced this entire investigation by saying it would be rudimentary so any statistical qualms I have are easily ignored. Are you not glad that I have such flexible morals?

Here is what we do know about Jones 147 big league plate appearances, spread almost equally between 2006 and 2007. Jones posted a 26.9% and 27.3% line drive rate each year. That is a very very good number, almost certainly too good to sustain itself. If they were done in seasons long enough to qualify, those numbers would rank 7th and 3rd highest respectively among single season line drive percentages over the past four seasons. In other words, unless you think Adam Jones is going to be the best line drive hitter in Major League Baseball next year, that number is going to come down.

How far down? For that, we turn to Jones’ Tacoma numbers where we get the benefit of an additional 886 plate appearances over the same time span. Those figures were lower in Tacoma, hovering a few ticks above 20%. That is still quite good if he can maintain that level. I am unsure if anyone has looked at how line drive rates move between AAA and MLB so for now, let’s just leave it as is and project a 22% LD% in 2008. Applying a (little less than standard) +11% to go from LD% to BABIP (not that robust, but again, good enough for this), we arrive at around a .330 BABIP.

We’re missing homeruns and strikeouts in order to figure out an estimate for batting average. Strikeouts are fairly straight forward; Jones Ks in about 29% of PAs over the course of his career. That’s going to improve with time, but in 2008 I would not count on much, let’s call it 28%. Jones hits groundballs at about a 40% clip, leaving us with 38% flyballs. Of those 38%. Jones smacked about one out of every five flybals over the fence in Tacoma, significantly less in Seattle. For 2008, I expect something in the middle and call it 13.5%. So in a 100 at bat sample, we expect something like 28 strikeouts, a little over five home runs and 67 balls in play yielding a little over 22 hits. Add it all up and you have a projected .272 average. It is worth reiterating that .272 accounts for a regression in line drive rate, virtually no progress in reducing strikeouts and just an average home run per flyball rate. The latter two points, middle especially, Jones could easily surpass.

For walk rate, I am just going to assume he holds at his 2007 level of 5.6% and that he both gets drilled and lays a sac down once every 100 PAs. That means 6.6 free passes per 100 PAs and 92.4 atbats giving us an on-base percentage of .318. For slugging, we’ve already anticipated homeruns, and using an average of 2006 and 2007 at both Tacoma and Seattle yields expected rates of 4.2 doubles and 0.9 triples per 100 at bats next season. Subtracting 5.1 from the 22.1 non-HR hits gives us 17 singles and a grand total of 48.63 bases in 100 at bats. Putting it completely together we have a .272/.318/.486 line for 2008. That is pretty close to ZiPS. The power output seems high to me, but again, you expect high power from somebody striking out nearly 30% of the time so if you think Jones is going to struggle hitting for power in 2008, you have to acknowledge that he might adjust and start going more for contact thereby reducing his strikeout rate and upping his batting average and OBP.

Turning to defense, Jones in 2007 played 176 innings and snagged 31 of 34 balls in zone and 8 out of zone. Taking the league rates for rightfielders (I understand Jones did not play exclusively in RF), the average fielder would have gotten to 29.5 balls in zone and 6 out of zone giving Jones 3.5 plays above average per 176 innings. Prorating that up to 1273 innings leaves us with 25 plays above average. That’s a 42 play improvement over 2007 Jose Guillen. Is that reasonable? Jones is a centerfielder playing rightfield, so we definitely expect him to be above average, but 25 plays? Half of that seems much more likely. That would roughly paint Jones as a league average centerfielder in terms of defense which seems about right for now.

One more time, there are huge sample size issues at stake here. Nonetheless I am just searching for a broad picture of what we might be looking at. Given the assumptions stated above the Mariners will move from a .290/.353/.460 hitter to a .272/.318/.486 hitter. Assuming 600 at bats (reasonable barring injury for a full time player) and using a simplified formula, we arrive at 92.7 runs created with Jones’ bat compared to Guillen’s 96.3 in 2007. So we lose 3.6 runs of offense. On defense however, we gained 29.5 plays, which works out to at least 23.6 runs using Tango’s established 0.8 runs = 1 play conversion. Funny how in the end we end up with nice round number, but there it is. -3.6 + 23.6 = 20 run improvement.