By Colin Moffat

Celtic have cantered to a second successive Scottish Premier League title, but the route to success was not all plain sailing.

On occasion, Gordon Strachan's side had to dig deep and pull on their enviable strength of character to salvage crucial points.

The champions have won an amazing 25 league games so far and 17 of those have been by a single goal.

BBC Sport looks back at the key games as Celtic refused to be knocked off their championship-winning course.

With 11 minutes remaining, Jan Vennegoor of Hesselink cracked in a 20-yard shot to seal a deserved win for the visitors.

Celtic were not at their best against a lively Falkirk side, but Aiden McGeady popped up to drive in a 86th-minute winner.

The home side moved 13 points clear at the top of the table thanks to a dramatic late own goal from Hearts goalkeeper Craig Gordon.

Celtic celebrate their last-gasp home win over Hearts

Hearts had been the more menacing team and went in front on 72 minutes thanks to Andrius Velicka.

But, with four minutes left, Jiri Jarosik headed in from a corner and, as Celtic pressed in the dying seconds, Gordon fumbled into his own net after appearing to gather a shot from Stephen McManus.

Hibs' aggression and pace saw them build a two-goal cushion through Ivan Sproule and Kevin Thomson, but the home side ran out of steam and Celtic ruthlessly hit back to snatch a share of the spoils.

On 70 minutes, Evander Sno coolly drilled a shot home after a positive run from Kenny Miller and, soon after, Aiden McGeady found the corner of the net with a precise 20-yard strike.

Once again, Celtic stormed back late on to rescue a game that looked beyond them.

David Robertson headed United into a surprise lead and Collin Samuel fired in following a Barry Robson free-kick.

But Darren O'Dea knocked home a Shunsuke Nakamura free-kick from six yards after 78 minutes and the Japanese playmaker later found the net with a sublime chip from 20 yards.

Celtic went a massive 17 points clear after another eventful comeback - this time at Tynecastle.

Jiri Jarosik (centre) was the match-winner at Tynecastle

Hearts started strongly and went ahead thanks to a rocket shot from Saulius Mikoliunas.

Celtic survived a few scares before Jan Vennegoor of Hesselink levelled from close range on the hour and Jiri Jarosik settled the match with a fine, low drive 20 minutes later.

Derek Riordan tapped into an empty goal to put Celtic in front, but Inverness threw everything at the visitors and Graham Bayne headed the equaliser after the break.

However, Celtic showed exactly what they are made of when Jan Venegoor of Hesselink lashed in an injury-time winner.

Just when it looked like Celtic's title party would be delayed for at least another week, Shunsuke Nakamura stepped up to curl in a wonderful injury-time free-kick.

Jan Vennegoor of Hesselink headed the visitors in front only for the battling hosts to level the game thanks to a Colin Nish goal.