The Mets' top prospect made his major-league debut Saturday, going 0-for-4 with four walks in two games. Buck is scheduled to return from paternity leave this week, but the team will keep d'Arnaud on the 25-man roster instead of Anthony Recker.
The rookie will remain the starting catcher even when Buck returns, with d'Arnaud potentially playing four or five times a week, according to Rosenthal. The Mets do not want to keep d`Arnaud in the majors only to bring him off the bench.
New York acquired d'Arnaud as the principal piece in the team's return from the Toronto Blue Jays for starting pitcher R.A. Dickey. The team may have promoted d'Arnaud earlier in the season, but he suffered a fractured metatarsal while playing in Triple-A, which sidelined him for nearly four months.
He hit while healthy in Triple-A, batting .304/.487/.554 in 78 plate appearances.