What is the difference between a myofibril and a myoblast? (In skeletal muscle)
Myoblasts are the embryonic precursors of myocytes (also called muscle cells). Myoblasts differentiate into muscle cells through a process called myogenesis.
A myofibril (also known as a muscle fibril) is a basic rod-like unit of a muscle cell. Muscles are composed of tubular cells called myocytes, known as muscle fibres in striated muscle, and these cells in turn contain many chains of myofibrils.
So, to answer your question, No. These two are different and one is the precursor of the other.