Another disappointing result saw Inter fail to put distance between themselves and Parma, who remain hot on their heels in the chase for European Football next season.
Walter Mazzarri made defensive changes following Sunday's 2-1 reverse against Atalanta. Juan Jesus returned from suspension and veteran Walter Samuel was drafted in from the bench. Yuto Nagatomo shook off a knock to start at left back. Samir Handanovic kept goal against his former club and President Erick Thohir was in the stands.
Simone Scuffet flew out of goal to punch clear a Jonathan cross inside the opening five minutes. Allan then charged down a shot from Esteban Cambiasso. Inter's lack of patience going forward saw them struggle to break down a stubborn Udinese.
Luis Muriel had the beating of Andrea Ranocchia and sprung the offside trap just short of the half hour mark. Samuel stepped across to block the shot and clear the ball. A loose ball by Jonathan saw Thomas Heurtaux balloon over from the edge of the box.
The game came to life five minutes before the break. Fredy Guarin wasted a free kick from distance, while Handanovic spilt a grasscutter from Bruno Fernandes. The rebound spun out to Emmanuel Badu, who sent his effort into the side netting from an acute angle near the byline.
Mauro Icardi was largely inconspicuous up front for the Nerazzurri. The Argentine managed to turn his markers, but lashed a high ball into the stands.
On the stroke of half time, Fernandes' teasing ball across the box just missed Muriel's feet by inches, as the forward came sliding in ahead of Ranocchia.
Ranocchia's cross almost looped into the net six minutes after the break. Ricky Alvarez was introduced to try and kickstart Inter, but sloppy play from Hernanes almost let Udinese in. Roberto Pereyra picked up the loose ball, only to see Handanovic comfortably go down low to smother his shot.
Hernanes tried to redeem himself with a set piece, but the Brazilian's free kick whistled past an outstretched Scuffet and finished inches past the post.
Juan Jesus switched sides with Ranocchia to mark Muriel and managed to hold off the Colombian in full flight. Inter increased the pressure and had the bit between their teeth. Hernanes was denied by Scuffet in full flight, before Samuel and Rodrigo Palacio both wasted free headers.
Icardi missed a glorious chance on 70 minutes. The forward turned over from four yards after getting ahead of his markers to intercept Nagatomo's shot. Inter lost Jonathan to injury, then suffered more bad luck when Palacio slipped after being put into a promising position by Nagatomo.
In the final five minutes, Palacio and Icardi combined to hook a shot at goal and Scuffet collided with Badu as he ran out to catch the ball. The 17-year-old shot stopper was having a game to remember. He denied Cambiasso at the death and Maurizio Domizzi hooked Danilo D'Ambrosio's follow-up header off the line.
Udinese were riding their luck. In stoppage time, Juan Jesus saw a shot deflect wide and Scuffet rushed out to punch away one final ball into the box by Hernanes. The misfiring Inter players were jeered off by their bemused fans at the final whistle.
Inter Milan: Handanovic; Ranocchia, Samuel, Juan Jesus; Jonathan, (D'Ambrosio 72) Guarin, (Alvarez 54) Cambiasso, Hernanes, Nagatomo; (Milito 86) Palacio, Icardi
Udinese: Scuffet; Heurtaux, Danilo, Domizzi; Widmer, Badu, Allan, Pereyra, (Maicousel 86) Gabriel Silva; Bruno Fernandes; (Lazzari 82) Muriel (Yebda 90+4)