U.S. energy stocks were among the market's biggest losers on Friday as the broad market sold off sharply amid growing consensus, at least today, that the Federal Reserve will raise interest rates before year-end.

Oil also fell further away from $50 a barrel, the recent psychological benchmark in a market that's seen crude fall by two-thirds in the last few years.

Oilfield services provider Diamond Offshore Drilling (DO - Get Report) was the worst performing energy stock on Friday, dropping 10.34% at the close of trading to $15.60 per share on lower oil prices. The company has been suffering from the downturn in the oil and gas industry, including early contract terminations on some of its rigs by Brazilian oil giant Petrobras recently that represented 8% of its backlog and 20 months of work.

The stocks of other oil companies fell as well. Oil and gas explorer Marathon Oil (MRO - Get Report) dropped 6.39% to $15.67 while services provider Transocean (RIG - Get Report) slipped 6.1% to $9.83, producer Murphy Oil (MUR - Get Report) slid by 6.08% to $27.94 and equipment provider National Oilwell Varco (NOV - Get Report) went down by 5.6% to $33.15.

The Energy Select Sector SPDR Fund (XLE - Get Report) , an exchange traded fund that tracks the sector, fell just shy of 4%.

Benchmark WTI crude settled Friday at $45.66, down 4.1%.