Yugas and Vishnu

The Avatars of Vishnu are partitioned among the Yugas in different variants.

There is the 4 – 3 – 2 – 1 partition

Satya Yuga – Fish, Turtle, Boar, Manlion.
Treta Yuga – Dwarf, Rama with the Ax, Rama
Dvapara Yuga – Krishna, Buddha
Kali Yuga – Kalki

In the Mahabharata is sayed, that with Krishna’s death Kali Yuga began.
After that Buddha should be assgined to Kali Yuga. That contradicts the 4 – 3 – 2 – 1 order.