The Dodgers designated Mike MacDougal for assignment Thursday and activated Ronald Belisario from the inactive list. Belisario had been serving a 25-game, league-mandated suspension for a positive drug test, and needed to be released, DFA’d or added to the major-league roster today.

Since that inevitability had been lingering since the season began, MacDougal had to be feeling the heat after he allowed five runs (all earned) in 5.2 innings for a 7.94 ERA. The 35-year-old right-hander also walked six and struck out four.

The Dodgers have 10 days to either add MacDougal to the 40-man roster, trade him, release him or place him on waivers (within seven days).

MacDougal originally signed a one-year contract with the Dodgers as a free agent in January 2011 and re-signed in January of this year. After posting a team-leading 2.05 ERA last season, his ineffectiveness began in spring training this year, when he posted a 7.88 ERA.

Belisario didn’t have the best spring either, allowing 10 runs (8 earned) in 9.2 innings for a 7.45 ERA. But today’s move comes as little surprise, as manager Don Mattingly often cited Belisario’s track record — which includes a 3.36 ERA and .221 opponents’ batting average in 128 major-league games.

The 29-year-old made four appearances with Triple-A Albuquerque and Single-A Rancho Cucamonga this season, including tossing 1.2 scoreless innings in his two appearances with the Isotopes. Belisario last pitched Wednesday and fired a scoreless frame against Oklahoma City.

Belisario said earlier this year that he believed the positive drug test came as a result of cocaine use.