In this article, we present a hybrid method to improve the performance of the Montgomery reduction by taking advantage of the Karatsuba technique. We divide the Montgomery reduction into two sub-parts, including one for the conventional Montgomery reduction and the other one for Karatsuba-aided multiplication. This approach reduces the multiplication complexity of n-limb Montgomery reduction from theta(n(2) + n) to asymptotic complexity theta(7n(2)/8 + n). Our practical implementation results over an 8-bit microcontroller also show performance enhancements by 11%.