Ah ah yeah he shaved his head for WC 2006 then he did it time to time (for what we care lol)
About glitches i noticed 3 things, like one possible reason you don't have any from what i saw : i played with the camera zoom to force the LOD on PES, and i noticed that on some distance, there wasn't any hair polygon disappearing/reappearing like dark magic lol. And it happens more often on the basic long range cam by default.
2nd thing i noticed : there's some special hairstyle which got more often that bug, on PES 5 for example even i changed Messi hair i assigned just to check and bam issue resolved for him.
3rd is that PES different graphics engine from Pes 2010 or 2009 if i remember well to 2014 version got far less issue with hair, only a dumb optic illusion due to emulation : lighting effect is different and when it's emulated you got hair shining with the sun or stadium night lightenning : it's not a glitchs it's simply that when you enhance the resolution so LOD too on Ps2, lighting seems to shine a bit too much.
I don't play version after Pes 2008 except WE 2010 Aoki or WE2010JL as the gameplay looks more like 2008 version, a bit simplified but stil pleasant + there's a lot of modes and original seasons patchs are pretty good. In terms of gameplay again i through PES 2014 was pretty different than PES before Ps3 version, but i played Pes 2013 too and it's not exactly the same neither : to me the game is better, more dynamic etc. i was surprised. Now all the version are a copy paste from PsP gameplay quite simplified and basic so they can make sequel without too much work i suppose.
Ain't A fan overall from 2009-2014 PS2 but i love to check OG season patch by curiosity as i'm a data/stats lover and i like to check created teams/players from scratch, Bundes especially i used to watch and like that league a lot so...
Now there's way too much interesting games deserving to play with on retro Ps2, i don't talk only about footy games, but as it's thread subject if you check only on football games for example Fifa Total Football i discovered is a game deserving a little more attention, a small campaign etc.
It's way different than Fifa Ps2 and with 360 analog movement (Iss got it too btw, FKingdom too). Thanks to the mate here who traduced the game and recently even all names
PS/
The version you're playing seems to already got a custom cam on the beginning a bit like melted TV cam and Long range not "wide" (so the cam by default, really nice cam btw i love it, you or the man who made the patch used the tool to mod cam, i would like to get the details about zoom/angle/height i can find it by opening the process with the tool, could you give me the patch details? Thanks mate