In another source I found a textual description of comparison of Yak-9 to 109G2 (the authors also present "criteria of similarities" analysis in mathematical notation, but I find it difficult to replicate all that in a regular post as it deals with partial differential euqations etc.).
"Aircraft construction in the USSR" by K.Yu. Kosminkov, Academician G.S. Bushghens, Lt Gen A.I. Ayupov, Dr.Tech.Sc. A.M. Batkov, Academician R.A.Belyakov, V.N.Bychkov, Dr.Tech.Sc. R.V.Sakach
(TsAGI publishing department, 1994)
p.106:
"By their horizontal maneuvering capabilities Yak-9, Yak-9D and Yak-9T had a significant advantage over the one cannon version of the Me-109G-2 up to alt of 3.5km and they could get on Me's tail in range of well-aimed fire in 2-3 turns. At the altitudes of 3.5-5.5 km the advantage was gradually decreasing and at the altitudes over 5.5 km the advantage went to the Me-109G-2. In maneuvers of the "combat turn" type (Wisk: essentially it's a chandelle/slanted vert loop) at alts up to 2km these variants of the Yak fighter had a slight advantage because of combination of horizontal and vertical maneuver, they could hold their altitude advantage. In the range of altitudes from 2 to 3.5 km the Yaks and the Me-109G-2 were practically equal in this type of a maneuver, the Me-109G-2 had an advantage above 3.5km. In general, these Yak fighters, using both horizontal and vertical maneuvers, could successfully wage an offensive air combat with the Me-109G-2 up to alt of 5km. The superiority of the Yak-9, Yak-9D and Yak-9T over the three-cannon version of the Me-109G-2 and especially over the FW-190A-4 and A-5 was even more dramatic."