Moving forward it's a mistake for the Mets to believe they can live with the mistakes Murphy makes at first, for those only counting errors, it's much more subtle then that. He is constantly out of position, effecting other players positioning and fielding while making then compensate for his deficiencies.
I actually feel bad for Murphy, the Mets truly did him a disservice, they decided not to go for a left fielder in a deep market and covered their tracks by promoting the home grown kid, off a 49 game hot streak straight out of AA. I believe eventually Murphy will become a Miguel Cairo type, but he shouldn't be the starting 1B next season...
Rob Neyer of ESPN takes on the idea of Murphy as a starting 1B, his position addresses Murphy's offense.
This season, 23 major league first basemen have enough plate appearances to qualify for the batting title. Among them, Murphy ranks 20th in slugging percentage and 22nd in on-base percentage. He's just not getting the job done, and isn't likely to. source ESPN