Stephen Welsh believes Sunday's 1-1 draw with Rangers revealed to him how far he has developed since his Old Firm debut last six months ago.
The 21-year-old centre-back made his second Celtic appearance against the Gers in a 2-0 league defeat at Parkhead last October.
Welsh has become a regular in the side in recent months and impressed against the new Scottish Premiership champions where the home side, under interim boss John Kennedy, were the better team but had to be content with a 1-1 draw. Alfredo Morelos' first goal in 15 matches against the Hoops cancelled out Mohamed Elyounoussi's opener.
Recalling that first Glasgow derby, Welsh said: "I think I have come a long way since then.
"I'm more mature, better on the ball and defensively. I'm probably more physical as well. I definitely felt a lot better.
"Everyone is fighting for positions in every area of the pitch. If you are playing you need to show why you've been picked and that's all I am doing right now.
"It definitely helps me having John Kennedy there. I've been with him for four or five years as a coach and now the manager.
"I enjoy going out and playing for him – and he knows what I can do. He trusts me to play in these games and that gives me a lot of confidence."
Celtic lost yet another goal to Rangers from a set piece in the 38th minute when Borna Barisic's corner was flicked on by Leon Balogun before Morelos stole into head in his 55th league goal for the club, coincidentally weeks after Rangers won their 55th title to stop Celtic making it 10 in a row.
Welsh said: "We defended well from open play but it was disappointing to concede from another goal from a set piece.
"We've done a lot of work on them but we need to go away and do more.
"We've conceded a lot from set pieces. The concentration levels need to be there 100 per cent of the time. There's been too many goals from corners."
Despite being nowhere near their best, the Ibrox side extended their unbeaten run in the league to 33 games, with five post-split fixtures remaining.
Boss Steven Gerrard was pleased with his side's resilience and told Rangers TV: "We have come on leaps and bounds in that department.
"We have played all season with character, we have played with ambition and when we have had to fight, we have fought.
"When we have had to play, we have played and we have always found a way to get results and that's the reason why we are unbeaten (in the league)."
