Billy McKay scored the only goal as Inverness Caledonian Thistle claimed their first ever league win at Celtic Park with a shock 1-0 win over the Scottish Premier League leaders.
In a low-key first half, Inverness limited their hosts to few chances with Kris Commons and Mikel Lustig wasting the best of their opportunities.
Inverness picked up the pace after the break and took a deserved lead in the 64th minute through McKay, although there was a hint of offside about his goal.
Georgios Samaras and Commons came close to an equaliser before Inverness spurned a chance to wrap up the points with McKay hitting the post and Aaron Doran's shot cleared off the line by Efe Ambrose following a quick breakaway.
The result continues Celtic's poor domestic form after a European match, with the Hoops failing to win any of their league matches on the back of their past three Champions League matches.
Despite falling to their third home defeat in seven league matches, Celtic remain top of the SPL after Aberdeen defeated Hibernian 1-0 to leapfrog the Easter Road side into second, although six teams are now within five points of the Hoops.
Elsewhere, St Mirren moved four clear of Dundee at the bottom with a 3-1 win over the Dens Park club.
Motherwell and Hearts ended goalless while Dundee United won 2-1 away to Ross County.
Premier League
Celtic 0 - Inverness1
Hibernian 0 - Aberdeen 1
Kilmarnock 1 - St Johnstone 2
Motherwell 0 - Hearts0
Ross County 1 - Dundee Utd 2
St Mirren 3 - Dundee 1
| P | W | D | L | F | A | Pts | |
| Celtic | 14 | 7 | 4 | 3 | 24 | 13 | 25 |
| Aberdeen | 15 | 6 | 6 | 3 | 20 | 14 | 24 |
| Hibernian | 15 | 7 | 3 | 5 | 26 | 21 | 24 |
| St Johnstone | 15 | 6 | 5 | 4 | 19 | 19 | 23 |
| Inverness | 15 | 5 | 7 | 3 | 28 | 26 | 22 |
| Motherwell | 15 | 5 | 6 | 4 | 22 | 19 | 21 |
| Dundee Utd | 14 | 5 | 5 | 4 | 18 | 19 | 20 |
| Kilmarnock | 15 | 5 | 4 | 6 | 24 | 20 | 19 |
| Hearts | 15 | 4 | 6 | 5 | 14 | 14 | 18 |
| Ross County | 15 | 3 | 7 | 5 | 17 | 22 | 16 |
| St Mirren | 15 | 4 | 3 | 8 | 20 | 28 | 15 |
| Dundee | 15 | 3 | 2 | 10 | 10 | 27 | 11 |
Other results
Division One
Airdrie 0 - Raith 0
Dunfermline 4 - Dumbarton 0
Falkirk 2 - Hamilton 1
Morton 1 - Cowdenbeath 0
Partick 2 - Livingston 0
Division Two
Brechin 4 - Forfar 1
East Fife 2 - Arbroath 1
Q’of the South 2 - Ayr 0
S’housemuir 0 - Alloa 2
Stranraer 1 - Albion 1
Division Three
Annan 1 - Clyde 3
Montrose 2 - Peterhead 0
Playing today
E. Stirling vs Berwick - 16.00
Elgin vs Rangers - pp