4/1 Upton solo hr -Sox win 8-2
4/3 Upton 2r hr - Sox win 7-4
4/5 Upton solo hr- Sox win 6-4
4/6 Upton 2 solo hrs- Sox lose 5-0 (would it have mattered, Boston only had 2 hits that day)
4/8 Upton solo hr- Sox win 3-1
4/14 Upton solo hr- Sox win 5-0
4/16 Upton solo hr- Sox win 7-2
4/18 Upton solo hr- Sox win 6-3
4/23 Upton hits 2 solo hrs(one in each game of a doubleheader) Sox lose 13-0 (neither would have mattered)
4/27 Upton solo hr- Sox win 8-4
5/13 Upton 2run hr- Sox did not play
5/17 Upton grand slam- Sox win 3-2
Boston could have actually lost some of these games if the guy whose spot he would of taken had superior and critical production.
19 of Uptons 29 rbi's came on home runs. The Red Sox are 10-4 on days when Upton gets an rbi.
We don't know what Upton would have done in Boston. And obviously the Red Sox will not continue to win more than 80% of their games when Upton hit's a home run.(he might even hit some vs Boston in the future) The game logs to this point do not indicate a single day that the Red Sox would have won an extra game when Upton hit a hr. Only on 5/5 does an Upton RBI potentially make a difference(Sox lose 4-3 and Upton had one RBI) There are other ways to impact games other than HR's and RBI's.
Also the Red Sox would not have had an extra hitter in each of these games if Upton was here. Someone else's production would be erased. Without making up a trade that did not happen, Daniel Nava would be the player whose 2013 production would be decreased. In fact, Nava might have been the guy lost from the 25 man roster. Carp may or may not have been acquired.
If Upton had been acquired, the Red Sox would have three outfielders paid to play regular. Gomes was here already and guaranteed to be on the roster on opening day. Keeping Nava as a fifth outfielder would make him the only real backup for Napoli. It is uncertain at best that the Red Sox would have made that commitment. If Carp was brought in or Overbay had stayed Nava would have no spot.
Upton would have raised the team salary this year without a departing contract in the trade. He also would have represented a future commitment, including having all of the leverage in the world to demand an extension at his price if he was even willing to drop his no trade to Boston clause.
We don't know what the Red Sox would have had to give up to acquire Upton. We don't know if the teams could have come to terms. The cost would have been tremendous.