A basketball is a sphere, not a circle. A circle is a plane figure. The same Hebrew word for circle in Isaiah 40:22 is also used in Job 22:14. There, in the KJV, it is translated as "the circuit of heaven." It is the same exact Hebrew word in both verses. So, is heaven a sphere? I don't think so. The ancients believed the earth was flat, a disc shaped area of land called earth. The earth was surrounded by the seas and the dome shaped skies ended where they met the ocean on the horizon. They believed the earth was supported by pillars. There was an underworld, called Sheol, where all the dead went when they died, no matter if they received a decent burial or not. It was considered the common grave of all mankind. Above, was the dome shaped sky, and above the sky was water. The Hebrews already had a word for sphere and it is used in Isaiah 22:18 and translated as a ball in the KJV.
Isaiah 22:18 He will surely violently turn and toss thee like a ball into a large country: there shalt thou die, and there the chariots of thy glory shall be the shame of thy lord's house.