LOS ANGELES (Hollywood Reporter) - Rebecca De Mornay is on track to co-star on ABC's new legal series from "The Practice" creator David E. Kelley.

She has signed to do four episodes of "The Practice," which serves as a springboard for the new show, with an option to continue on the new series as a regular.

She will play a tough, capable attorney working for Crane, Poole & Schmidt, the law firm that represents Alan Shore (James Spader) in his wrongful-termination lawsuit against Young, Frutt & Berluti. De Mornay replaces Fay Masterson, who was originally cast in the role.

In the new show, said to be lighter in tone than "The Practice," Shore and Tara Eilson (Rhona Mitra) join Crane, Poole & Schmidt, where senior partner Danny Crane is played by William Shatner.

De Mornay, who most recently co-starred in the feature "Identity," next appears in "Heart of Summer."

THE PRACTICE (ABC) - Vincent Pastore ("The Sopranos") has signed on to appear in three of the show's final four episodes this season. He'll play Lenny Pescatore, a bully of a lawyer who faces off against Jimmy Berluti (Michael Badalucco). His contract also includes the option to become a regular on "The Practice's" forthcoming spin-off.