Jeffrey Gundlach, Wall Street's bond king and a respected markets forecaster, believes that the rally in Treasurys reached a crescendo this week and will likely pause.

In a Twitter post Wednesday, he said that such a dramatic swing in Treasury prices may have as much to do with crowd mentality as anything else.

"Long maturity US Treasury price action today was consistent with a blowoff momentum top," the founder and chief executive officer of DoubleLine Capital wrote. "I suspect buyer's remorse will set in fairly soon."

Gundlach tweet

Since prices move inversely to yields, that means the drop in rates that's spooked the financial markets is likely over for now, according to Gundlach.

His tweet followed a volatile session on Wall Street as more declines in long-term Treasury yields reflected underlying concerns surrounding the global growth outlook. Between an entrenched U.S.-China trade conflict and export weakness in Europe, investors have looked to more defensive options throughout May, ditching equities in favor of reliable returns in the Treasury market.

That's kept consistent pressure on stocks and yields alike, with the 10-year Treasury note rate down about 25 basis points this month, a notable move for a benchmark for financial instruments like mortgage rates.

It's also led to the inversion of the yield curve, a market phenomenon that occurs when long maturity yields fall below those of shorter duration debt. The spread between the 10-year yield and the 3-month rate held in negative territory on Thursday. Many economists and investors see yield curve inversions as predictors of future recession.

If Gundlach is right, however, investor demand for U.S. debt may soon abate as a 5.5% decline in American stocks finally draws some traders back into equities. That appeared to be the case Thursday morning as stock futures pointed to a slightly higher open and yields ticked higher across the board.

Gundlach, known for his investment acumen in the fixed income markets, manages assets of more than $130 billion at DoubleLine, according to its website. He told CNBC this month that the stock market is likely stuck in a bear market.