The Angels acquired minor league catcher Logan O’Hoppe in exchange for Marsh while the Cubs received minor league pitcher Ben Brown for Robertson.
Robertson, 37, is in the midst of a resurgent year. He allowed just 23 hits in 40⅓ innings while racking up 14 saves and a 2.23 ERA for the Cubs well below .500. He has closing and setup experience, so the Phillies can use him in either role.
Marsh will likely take over in center field for the Phillies, who have been looking for an answer to the position for most of the season.
Marsh, 24, is hitting .226 with eight home runs and 37 RBIs this season.
Robertson previously pitched for the Phillies in 2019, when he was 0-1 and had a 5.40 ERA in 6⅔ innings pitched before injuring his elbow.
O’Hoppe, 22, is hitting .269 with 15 homers and 45 RBIs at Double-A Reading this season.
Brown, 22, is 3-5 with a 3.08 ERA in 16 appearances (15 starts) for Class A Jersey Shore.
Familia, 32, signed by the Phillies in the offseason, has a 6.09 ERA in 34 innings pitched this season. Herrera, meanwhile, is hitting .238 with five home runs and 21 RBIs this season.
The Phillies (55-47) currently hold the last wildcard spot in the NL with a one-game lead over the Cardinals of St. Louis.
ESPN’s Jesse Rogers contributed to this report.