Drawing on the theories of knowledge recombination, we aim to unpack the essential tension between tradition and innovation in scientific research. Using the American Physical Society data and computational methods, we analyze the impact of knowledge spanning on both citation counts and disruptive innovation. The findings show that knowledge spanning has a U-shaped impact on disruptive innovation. In contrast, there is an inverted U-shaped relationship between knowledge spanning and citation counts, and the inverted U-shaped effect is moderated by team size. This study contributes to the theories of knowledge recombination by suggesting that both intellectual conformism and knowledge recombination can lead to disruptive innovation. That is, when evaluating the quality of scientific research with disruptive innovation, the essential tension seems to disappear.