The rally in base metals this year could soon run into headwinds as soaring prices and bullish sentiment clash with the reality of softer demand from manufacturers, especially in China, according to Goldman Sachs Group Inc. “The real producers on the ground, they start to respond negatively,” Trina Chen, co-head of equity research, said in a Bloomberg Television interview. “We’re seeing some pullback in demand.” Most Read from Bloomberg Trina Chen, Co-Head of Greater China Equity Research and China Basi ...