(Reuters) -Top U.S. refiner Marathon Petroleum ( MPC ) beat fourth-quarter profit estimates on Tuesday, as strength in its midstream and renewable diesel segment helped offset a slump in refining margins.

The refiner's midstream segment reported an adjusted core profit of $1.71 billion in the quarter, compared with $1.57 billion a year earlier, benefiting from accretive contributions of its recently acquired Utica and Permian basins assets.

The company's MPLX unit acquired Utica assets from pipeline operator Summit Midstream Partners for $625 million last year.

However, the company's refining and marketing margin was down at $12.93 per barrel in the quarter, compared with $17.81 per barrel from a year earlier.

Quarterly U.S. refinery margins, measured by the 3-2-1 crack spread, have been down on an average from a year earlier, touching as low as $15.04 in mid-December.

On an adjusted basis, the company reported a profit of 77 cents per share in the quarter, compared with the analysts' average estimate of 2 cents per share, according to data compiled by LSEG.