Who was the mascot of SEGA before "Sonic the Hedgehog"?

Before Sonic the Hedgehog became the iconic mascot of Sega, the company had another character named Alex Kidd as their primary mascot. Alex Kidd, a small boy with large ears, starred in several platform games during the 1980s, most notably "Alex Kidd in Miracle World." However, Sonic the Hedgehog was introduced in 1991 and quickly gained popularity with his futuristic design, blazing speed, and adventurous gameplay, eventually surpassing Alex Kidd in terms of popularity to become Sega's new flagship mascot.