Izaguirre returned to Celtic for a second Parkhead spell earlier this summer.
Celtic remain favourites to progress from the Europa League play-off round despite a disappointing 1-1 draw against Suduva on Thursday.
Celtic welcome the Lithuanian champions to Parkhead in six days' time, needing only a win - or 0-0 draw - to seal their place in the group stage.
But some Bhoys fans are unhappy with their side's failure to bring back a win from Marijampolė, which would have made next week's task slightly easier.
And the decision to bring on Emilio Izaguirre - a left-back - in favour of a more offensive substitution with 24 minutes remaining proved particularly irksome.
The Honduran returned to Celtic earlier this summer, a year after he left Glasgow for Al-Fayha.
But while Izaguirre remains a popular figure within the Bhoys' fanbase, some believe that he is not the same player he was in his first Parkhead spell.
This is what they're saying on Twitter...
Darren @ocbhoy: Can cuddle as many fans as he wants Izaguirre is still a ******* liability
Brendan Donaghy @BrendanDonaghy: What the **** were Celtic thinking bringing Izaguirre back? Baffling.
Nohar @JordanNohar67: izaguirre is a ******* clown anawl take that jersey off him
No excuse. He needs to get the intensity levels back up. Should have got Sinclair on the park at some point. Izaguirre left wing back just isn’t going to cut it for me. Can’t be doing that at this or at any level.— Murray Macdonald (@DMMacdonald96) August 23, 2018
Izaguirre looks like he’s rubbed wet look gel all over his body.— wardy (@Bogroleum) August 23, 2018
Emilio is nowhere near the quality we need at Celtic either— Josh Gilston (@JoshG59778539) August 23, 2018
Izaguirre sends his regards— Jon Boy (@JonBoy__9) August 23, 2018
Was bringing back Izaguirre a good decision by Celtic?
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