Hanley Ramirez, Randy Choate, Brandon League, Shane Victorino, Joe Blanton, Adrian Gonzalez, Josh Beckett and Nick Punto squeezed into Mattingly's office in a follow-up to the full team meeting Mattingly held after Thursday night's 2-0 loss to the D-backs.
Mattingly declined to discuss details of the Friday meeting with the new players other than to emphasize that nobody had done anything wrong.
But earlier he discussed the challenges of turning over one-third of the roster during a pennant race and the urgency to get the Dodgers playing as a team with 30 games remaining.
"We've got eight new guys that haven't been through Spring Training or the fight to this point," Mattingly said. "Just making sure everybody's on the same page as everybody else."
Although the Dodgers could use another reliever with the uncertain health of closer Kenley Jansen, no deal appeared imminent approaching Friday night's 8:59 p.m. PT waiver deadline to add players who would be eligible for the postseason.
Mattingly said that when rosters expand Saturday, the Dodgers will likely promote Tim Federowicz from Triple-A Albuquerque to be a third catcher and Javy Guerra for bullpen depth.
Disabled shortstop Dee Gordon is eligible to return from his rehab assignment Monday, although Mattingly said earlier this week that Gordon won't start when he returns, with Ramirez now at short and Luis Cruz excelling at third base.
When Albuquerque's postseason play is done, the pool of players that might get callups includes Bobby Abreu, Tony Gwynn, Stephen Fife, Josh Wall, John Ely, Elian Herrera, Alex Castellanos and Scott Van Slyke.