Liev Schreiber’s new Showtime series, “Ray Donovan,” proved its ratings mettle in its second week.

Sunday night’s episode averaged 1.6 million viewers — up 15 percent from the series premiere, which in itself set a record for the most-watched series premiere in Showtime history.

And now “Ray Donovan” holds the title as the network’s only new series to grow its viewership in its second week — and that includes the critically acclaimed “Homeland.”

The show, in which Schrieber plays a “fixer” for the rich and famous in LA, averaged 2.2 million viewers for the night, when two repeat telecasts (11 p.m., 1 a.m.) were factored in.

Jon Voight, Katherine Moennig and Paula Malcolmson co-star in the series.

Showtime’s other current series, “Dexter” — which is in its final season — also had a good night on Sunday, snaring 2.5 million viewers and averaging another 500,000 more viewers when its repeats were factored in.