Veteran fund manager Larry Glazer is worried too many investors are in the wrong trade.
His concerns stem from the crucial role big technology stocks are playing in the record rally. If investors don't diversify away from some of the year's biggest winners now, Glazer believes they're going to feel a world of pain.
"Ten names driving half of the return of the in the first seven months of the year. They want to hear that can continue because it's a neat and convenient story, " the Mayflower Advisors managing partner told CNBC's "Futures Now " last week. "That divergence can't continue."
Glazer, who has almost $3 billion in assets under management, referred to Amazon, Microsoft, Apple, Netflix, Facebook, Alphabet, Mastercard, Visa, Adobe and Nvidia as some of the biggest names behind this year's index imbalances.
These so-called FANG [Facebook, Amazon, Netflix, Google] stocks are "not the U.S. economy," he added. "Investors need to make that distinction. They don't want to hear it."
He also suggested sentiment in the market was getting out of hand.
"Investors are starting to feel a little bit confident here. Maybe overconfident. Maybe almost little bit invincible. And, we're starting to see some laziness creep into investment strategies," said Glazer. "That laziness is precisely why at this moment we need the Honest Abe conversation."
It sounds like a pretty bearish argument. However, Glazer isn't classifying himself as a bear.
"It's not so much that we can't be bullish on the broad U.S. economy because when you look at jobless data, it's really strong. You look at GDP, it's strong. Consumer confidence [is at a] multi-decade high. All of those things are really bullish," he said. "It's really more a matter of the leadership of the market changing."
According to Glazer, investors should shift their exposure to value names, particularly groups that typically do well as inflation rises and the dollar weakens. He likes financials, energy and gold. Plus, he suggested hard hit emerging markets are showing signs of a bottom.
"You are starting to see emerging markets coming back. So, that global story is intact. The divergence is dissipating. That's what you really want to see to see the market go higher, " he added.
His thoughts came as stocks rallied to all-time highs, with the Dow reaching its highest level since January 26.
"It's so convenient at a cocktail party to say 'I want to stick with the Nasdaq. I'll stick with the S&P. I don't want to know about anything else. Asset prices will go up. There will be no inflation,' " Glazer said. "It doesn't work that way. You got to get into the global picture."