(CNBC) Unless the Fed shocks investors with a hawkish tone, oil conceivably could be a bigger factor for credit markets this week than the Fed’s first hike in nine years.

“There is definitely an obsession over oil and what that means for the next trend for both the stock and bond market, and the Fed should not really want to get in the middle of that tussle,” said George Goncalves, head of rate strategy at Nomura.

Falling oil prices have hammered stocks and bonds of energy companies, and market fears about its impact on corporate balance sheets got worse when crude plunged below $40 a barrel last week. The most affected corner of the credit market has been high yield or “junk bonds,” hit broadly but with energy and materials names slammed even more.

“I think it’s going to be pretty hard for high yield to rally until oil gets its legs,” said Rick Rieder, BlackRock chief investment officer of fundamental fixed income. He said the bond market has already mostly priced in the Fed’s rate hike.

“It’s pretty hard for rates to move dramatically. I think if you drift higher, but there’s a shock to any part of the world, it would bring us back to 2 percent. I don’t think we’re going to see a 3 percent 10-year next year. I think we’ll see mid- to high-2s,” Rieder said of Treasury yields.