Russia's US$63 billion of investment-grade corporate bonds may find a new buyer in Rogge Global Partners if they follow the sovereign in getting downgraded to junk.

Rogge may consider adding OAO Lukoil notes if the credit rating of Russia's second-largest oil producer is also lowered to Ba1 at Moody's Investors Service, said David Newman, the head of global high-yield debt at Rogge, set up in 1984 and managing $55 billion in at least 12 funds. According to Newman's calculations, Russia's share in the Bank of America Merrill Lynch Global High Yield Index may rise to as much as 5.5 percent from 1.9 percent once its corporate bonds are downgraded.

"Clearly the big names are coming down, so Russia will become a bigger part of a global high-yield benchmark," Newman said by email on Wednesday from London. He said he usually looks to keep his portfolio within 10 percent of the Merrill Lynch gauge. "If you are a benchmark hugger, there will be demand," he said.