The Bhoys faithful were delighted with the Australian but have yet again been left questioning their left-back's crosses.
Indeed, 22-year-old Tom Rogic not only started but impressed and got a goal for the Bhoys. Could the Australian midfielder finally be making the impact he promised to when arriving at Parkhead?
Celtic fans were naturally delighted with him on Twitter after their side's 2-0 win over Partick Thistle.
Some things, however, don't change. Namely Emilio Izaguirre's crossing.
Indeed, Rogic's excellence on Sunday afternoon was rather offset by another display from the left-back that infuriated the Bhoys faithful. Here, firstly, is how Celtic fans reacted to Rogic's performance...
Rogic off now and a solid shift & an excellent goal.. Making steps forward! #celtic— iamrosshamilton (@iamrosshamilton) August 9, 2015
A very dominating performance from #Celtic in the 1st half. Great to see Rogic score his first goal for the club, and what a belter it was.— Terry O'Brien (@terry_obrien86) August 9, 2015
Great to see Rogic getting a game in the first team, getting a goal is an added bonus. #Celtic— Felix (@stormstryder85) August 9, 2015
But their feelings towards Izaguirre were a little different. It's so far so good from Celtic in terms of their league and European season, although the big test will obviously come during their Champions League play-off against Malmo.
Should they make it through that, Celtic fans may be asking Ronny Deila to sign a new striker - and a new left-back.
There's certainly plenty of negativity towards their current left-back at the moment, as the Twitter reaction to 29-year-old Izaguirre's display at Partick Thistle demonstrates...
Izzy is one of the worst crossers of the ball I have ever seen. #celtic— Danny Harrison (@dannyaharrison) August 9, 2015
You would think after all this time Izaguirre would be able to cross a decent ball into the box— Paul Nash (@paulnashh) August 9, 2015
No even Jesus could get himself on the end of Izaguirre's crosses— Brucie Bonus (@Brucehillbhoy) August 9, 2015
Surely Celtic have to replace Izaguirre with a better left back?— Andrew Bargh (@andy_bargh) August 9, 2015