Preston chipped in six points (3-6 FG, 0-1 3Pt), four rebounds, six assists and one steal across 17 minutes during Friday's 131-102 loss to the Clippers.
Preston was waived by the Grizzlies on Wednesday.
Preston signed a one-year contract with the Grizzlies on Monday.
Preston tallied 13 points (5-13 FG, 0-1 3Pt, 3-3 FT), 10 rebounds and five assists in 27 minutes during Wednesday's 83-74 Summer League win over the Clippers.
Preston finished with 16 points (6-17 FG, 2-8 3Pt, 1-1 FT), five rebounds and one assist in 29 minutes during Monday's 108-101 loss to the Memphis Hustle.
Preston finished Sunday's 122-99 loss to the Cavaliers with 12 points (6-12 FG, 0-3 3Pt), eight assists, three rebounds and one steal in 37 minutes.
Preston has been recalled from the G League and is available for Thursday's game against the Spurs.
Preston finished with 21 points (9-19 FG, 3-7 3Pt), four rebounds and four assists in 33 minutes during Monday's 106-93 loss to the Motor City Cruise.
The Clippers assigned Preston to the G League's Ontario Clippers on Monday.
Preston finished with 29 points (9-13 FG, 6-9 3Pt, 3-3FT), eight assists and three rebounds in 36 minutes during Sunday's 123-110 loss to the Sioux Falls Skyforce.