12:22pm: The deal is "getting pretty close," a source tells MLB.com's Alden Gonzalez (Twitter link). Though he was discussed in a separate trade with the White Sox and Angels, Kendrick is not part of this deal, Gonzalez adds.
12:10pm: USA Today's Bob Nightengale reports that the three teams are optimistic about their chances of finalizing the trade (Twitter link). Meanwhile, Nick Piecoro of the Arizona Republic agrees with Gilbert's report from below, noting that Arizona would receive one prospect from the Angels and one from the Sox (also on Twitter).
11:38am: MLB.com's Steve Gilbert tweets that Arizona would receive a pair of good prospects in addition to Trumbo.
11:27am: Dan Hayes of CSN Chicago (via Twitter) hears that the talks are definitely ongoing but are still in the preliminary phases. The three sides are making some progress but a deal isn't close at this time, Jeff Fletcher of the Orange County Register agrees (on Twitter).
11:02am: The Angels tried to land Santiago from the White Sox in talks for Howie Kendrick, tweets Bill Shaikin of the L.A. Times, but they're now focused on getting him as part of this three-team deal.
10:50am: ESPN's Keith Law reports (via Twitter) that the Mark Trumbo talks between the Diamondbacks and Angels have expanded to include the White Sox, with a potential framework sending Adam Eaton to Chicago and Hector Santiago and Tyler Skaggs to the Angels.
Parting with Skaggs and Eaton would be a steep price to pay in order to play Trumbo out of position at a corner outfield spot, but reports have indicated that the D-Backs are "determined" to leave Orlando with either Trumbo or Shin-Soo Choo in tow, and the financial commitment required to add Choo would be significant. Adding Skaggs and Santiago would be a tremendous win for Angels GM Jerry Dipoto, who has been in the market for controllable young starters for months.