Milan Skriniar bailed out goalkeeper Samir Handanovic and maintained Inter's winning run in a 2-1 victory at Hellas Verona to keep the pressure on title rivals Milan.
The Nerazzurri were made to work for their seventh straight Serie A success - a result that took them two points above their city neighbours, at least until the Rossoneri hosted Lazio later on Wednesday.
Skriniar's 69th-minute header proved decisive after Handanovic had gifted an equaliser to Ivan Ilic, cancelling out Lautaro Martinez's second-half opener.
The defender's first Serie A goal since February 2018 brought to a close a promising first section of the season for Antonio Conte's side, able to take in the Milan match and enjoy Christmas regardless, firmly back in the Scudetto hunt.
A stale first half did not produce a chance of note until the 26th minute when Federico Dimarco got in on the left but found Handanovic to be his equal from a tight angle.
Giangiacomo Magnani enjoyed his physical battle with Romelu Lukaku, but a slack pass set Inter away and the striker squared for Martinez to stab goalwards and draw a sharp save from Marco Silvestri.
Verona could not keep the Argentina international at bay again six minutes after half-time as he ran across Matteo Lovato to meet Achraf Hakimi's cross and aim a volley beyond the goalkeeper and in off the post.
An inexplicable error let the home side back into the match, however, as Handanovic dropped a simple Marco Faraoni centre and Ilic was alert enough to beat Skriniar to the loose ball inside the six-yard box.
If Handanovic looked to his centre-back to share the blame, Skriniar responded in impressive fashion with a towering header that left Silvestri rooted and restored an Inter lead they this time would not relinquish.