Well, looking into that would take far more time than I have, in order to filter everything by dates for each player.
But looking at first half vs second half stats for the team as a whole, the offensive numbers are as follows:
1st half
.259/.328/.443/.771, wRC+ 94, WAR 10.7
2nd half
.248/.331/.447/.778, wRC+ 96, WAR 8.4
JD was acquired by the Dbacks on July 19th, so the above split is not quite exact.
The numbers in the second half are very slightly better, but just adding JD's bat to the line up should improve overall numbers over a weaker bat.
In short, you can't conclude anything from what I've posted.