Don't buy (the wrong) bonds: BlackRock credit pro

Where to take interest rate risk
Where to take interest rate risk

Investors should not put a large part of their portfolio in bonds in this interest rate transition period, said Jeff Rosenberg, chief investment strategist for fixed income at BlackRock.

"It's not just don't put money in bonds. You need to rethink how you put your money in bonds," Rosenberg said Tuesday on CNBC's "Squawk Box." He spoke as the Federal Reserve began its two-day policy meeting.

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"If you look at where we are going, it's the most obvious thing in the world," he said. "This year is a transition year. We're leaving quantitative easing. We're having a debate on when [Fed] interest rates are going to go higher."

Most investors have gone into the front end of the yield curve, he said. "The short duration trade has been the preferred trade."

But that's exactly where investors could be the most vulnerable. "When you get to that point in the interest rate cycle, where are the biggest increase in interest rates to be found? In the short end of the curve. This is where everybody thinks they're safe."

Don't be afraid to take interest rate risk, Rosenberg advised, just take it elsewhere. "The most surprising out-of-consensus call that we had this year was the back end of the yield curve would be the best part of the yield curve to be in, because when we started the year at 3 percent 10 year Treasurys, that's not a bad yield in this growth environment."

By CNBC's Matthew J. Belvedere