How many 50 goal scorers have gone on to play at 44?

Zero. Okay, how about age 43? One. Messier. Scored 18 goals. Age 42? Three. Messier, Andreychuk, Bucyk. (scored 18, 6, 5.) Age 41? Bucyk, Recchi, Messier, Bobby Hull, Gary Roberts. (scored 20, 18, 7, 6, 4.)

Is Kovalchuk in the same league as those guys? Well, yes, he's in the NHL! Sorry. Other than that, no, he's not.