A round mower deck for a rotary lawn mower may have a leading edge extension near the sides of the deck to improve cutting performance at the edge of a cutting swath. The leading edge extension may be mounted on an otherwise curved leading edge of a mower deck within the last few inches of the deck width. The leading edge extension may overlap some portion of the cutting stroke of a blade, and may prevent grass from being deflected away from the blade, resulting in a poor cut near the edge of a cutting swath. In some cases, the extension may be removable and may be added to an existing mower deck.
