The Dungey cycle is a fundamental concept in understanding magnetosphere convection in the presence of the interplanetary magnetic field (IMF). It explains that the convection within the closed part of the magnetosphere is primarily driven by magnetic reconnection in the nightside magnetospheric tail. Here we provide evidence that magnetospheric convection can also be driven solely by dayside magnetic reconnection, specifically through the ionosphere's two-cell convection. The enhanced convection progresses from the dayside to the nightside and responds rapidly, within 10-20 minutes, to a southward turning of the IMF. Uncovering this physical process provides new insights into the driving mechanisms behind planetary magnetosphere convection.