Oliva RF -2e12 Fielder

Recently I have been bringing in a defensive CF in late innings and in doing so HAL has moved Oliva to LF even though he isn't carded to play LF. How will his defensive abilities in LF be graded; 2e12? or worst because he isn't carded to play left?

When Hal does this with the CD-ROM the centerfielder retains his ratings.

thanks!