SAN DIEGO — The names of the two prospects the Phillies will receive from Los Angeles for Jimmy Rollins remain shrouded. A source familiar with the situation said one of the players could come from a separate Dodgers trade with another club.

That is the reason for the delayed announcement.

Zach Eflin, a 20-year-old righthander going from the Padres to the Dodgers in the Matt Kemp trade, is one possibility. The Phillies "expressed recent interest" in Eflin, according to a Foxsports.com report.

But a formal announcement of the Rollins trade may not happen until Friday because the Kemp trade requires approval from the commissioner's office for a significant money exchange. And both teams must review medical data for players with sizable injury history.

The other player in the trade is expected to come from within the Dodgers' minor-league system.

Eflin pitched at single-A Lake Elsinore last season and posted a 3.80 ERA in 24 starts. He was a first-round pick (33d overall) in the 2012 draft. He was not ranked by Baseball America among San Diego's top 10 prospects last season.

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