Martin O'Neill closed the gap on Scottish Premiership leaders Hearts as he delivered one final victory for Celtic.
Daizen Maeda's brave 11th-minute header proved enough to hand O'Neill a 1-0 victory over Dundee in his farewell match before making way for Wilfried Nancy, whose appointment was confirmed less than an hour before kick-off.
It was O'Neill's seventh win in eight matches since returning to Celtic Park 20 years after his initial spell in charge ended.
Celtic were eight points adrift of Hearts when O'Neill and Shaun Maloney were placed in interim charge in the wake of Brendan Rodgers' sudden exit in late October.
The 73-year-old leaves with Celtic now trailing the league leaders on goal difference with a game in hand.
O'Neill's players could have given their manager a less stressful swansong but could not build on their flying start and Dundee caused some nervy moments for the home support.
That included a sparsely-filled standing section with the bottom six rows blocked off following the extended and indefinite ban handed to the Green Brigade on Tuesday.
Anti-board chants rang out along with tributes to O'Neill in a reminder that Nancy inherits a disunited club despite the platform to challenge in the league and Europa League, as well as a Premier Sports Cup final to look forward to in
his third match. His first two come against Hearts and Roma.
Celtic were quickly on the front foot and Maeda and Reo Hatate threatened from long range before the breakthrough.
Hyun-jun Yang continued his rejuvenation under O'Neill by forcing a save from Jon McCracken after a lofted pass from Hatate and Maeda headed home the rebound before being caught by the head of Luke Graham in a hefty collision.
Celtic played with 10 men for several minutes before the Japan forward re-emerged from the tunnel sporting a bandage and a black eye.
Celtic continued to press and Arne Engels and Yang had chances before Marcelo Saracchi forced a good save. The Uruguayan left-back soon went off with what looked like a recurrence of a hamstring injury, with Kieran Tierney a straight
replacement.
There was one first-half scare for Celtic when Simon Murray hit the bar after Liam Scales' short headed pass back. The offside flag went up after Kasper Schmeichel saved Cameron Congreve's follow-up.
Celtic also started the second half well. Maeda could not steer a rebound on target following Luke McCowan's effort and Hatate saw a shot saved after some impressive football.
Dundee began to threaten midway through the half. Substitute Ashley Hay was released by a long ball, shrugged off Scales' attempt to bring him down and tried his luck from an ambitious angle. Schmeichel blocked his weak effort.
Finlay Robertson then tried his luck from 50 yards after Schmeichel came out of his box and sliced a clearance but the goalkeeper raced back to save, comfortably in the end.
Dundee kept the pressure on until Maeda hit the post on a stoppage-time breakaway, before the full-time whistle prompted chants of "Martin O'Neill" around Celtic Park.
