كتب : Omar AbdelAziz
The league leaders were about to suffer their first defeat this season only to be saved by a Hernan Crespo header in the 67th minute.
Christian Obodo had given Udinese the lead two minutes after restart.
Roberto Mancini had to try new options in midfield as he missed suspended Dejan Stankovic as well as injured duo Esteban Cambiasso and Patrick Vieira.
Inter controlled a goalless first half and were unlucky not to take the lead as they came close through Luis Figo, Zlatan Ibrahimovic and Adriano efforts.
However, the visitors stunned the home side with a sizzling start to the second half.
Christian Obodo received a Cesare Natali pass in the box, and the Nigerian produced a superb bicycle kick to give the visitors an unlikely lead in the 47th minute.
Udinese held on to the lead until the 67th minute when Crespo directed Maxwell's cross into Morgan De Sanctis' net to salvage the point and record his 15th career goal against the Udine side.
Inter maintained the 14-point lead over second placed Roma who came back from two goals down to secure a 2-2 draw at Chievo.
Udinese are the only Serie A team Inter failed to beat this season as Alberto Malesani's side were the last to take points away from the league leaders after a goalless draw back in October.