This is not really a pressing issue at the moment, but some future posts are going to build off this concept and it's bound to come up in the future, so consider this a bookmark post. Feel free to refer back when the inevitable happens.
Jose Lopez the last two seasons has posted WARs of 2.0 and 2.6 and was at 2.1 in 2006. His dreadfully awful 2007 really mars the picture, but the outline is still clear. While Lopez has the potential to crater offensively at times, always a possibility with free swinging righties in Safeco Field, he is a decent bet to produce a final 2010 line close to this (figures are relative to league average):
0 run bat
0 run glove
+2.5 positional adjustment
+20 replacement level
That's a 2.25 WAR player, slightly above average. For the $2.5 million that he's slated to earn in 2010, that's a real bargain, on the order of an $8-10 million asset. What would happen if we moved him to first base however?
Well, he would no longer be playing second base, for starts. Second base is a nearly perfect position for Jose Lopez's defensive skill set. He has average range for a second baseman and he turns the double play well. Lopez's problem are the retarded errors that he tends to make, seemingly stemming from lapses in concentration that, along with his hacktastic hitting style, serve to profile him as a lazy player. Moving to first base would probably cut down on his error rate, as first baseman get involved in much fewer plays of the type that lead to errors and their dropped catches are always blamed on the thrower for some reason.
I would expect Lopez then to gain about three runs in defensive value from reduced errors and probably three runs or so from increased range. He would also lose about a run from no longer being involved in double play turns. In the end, about a five run boost in total seems reasonable. Incidentally, that's in close range to the increases in defensive value that Miguel Cabrera (from third base) and Albert Pujols (from left field) saw after moving to first base. Furthermore, moving to first base from a non-catcher or DH role seems to offer no increase in hitting skill.
The downside is that first base carries a 12.5 run penalty with it as it is among the easiest of all positions to fill. Coming from second base, with its 2.5 run bonus, Lopez would see an instant 15 run drop in positional value. Those extra five runs in defensive skill, from being compared to first baseman instead of second baseman, is not enough to make up the difference. Lopez's likely projection at first base would look approximately like this:
Lopez, at first base:
0 run bat
5 run glove
-12.5 positional adjustment
+20 replacement level
Moving Lopez to first base has the net effect of chopping about a whole win off his value. That $8-10 million asset is now a $4-5 million one. In addition, that 1.25 WAR or so does not constitute much of an improvement over what we would expect from Jack Hannahan or Mike Carp, much less from any outside options that may or may not be available.
I've been against it for years, every time it gets brought up in the media, or here, or anywhere. Jose Lopez at first base is a bad idea. It's an inefficient use of resources and represents a fractional upgrade at best over current in house options at the cost of opening a much more difficult hole to fill. If the Mariners find themselves in a situation in which Jose Lopez's services at second base are no longer desired or needed, then a trade is almost certainly going to be the optimal route.