Mourinho's side failed to turn their domination into more goals and things got edgy late on when Saville's shot evaded Gazzaniga who seemed slow to get down.
Liverpool were left frustrated by Championship side Blackburn Rovers who defended heroically to draw 0-0 at Anfield.
After over 500 appearances, 100 goals and countless mesmerising dribbles, Ryan Giggs, Manchester United's prince of wingers, has suddenly become a target for the club's boo-boys.
Arsenal's defence of the trophy ended with something of a whimper as Mikel Arteta's side struggled with repeatedly sloppy defending.
The index had risen over 585 points in the previous three sessions.
Holders Manchester City began their assault on the FA Cup with a 4-1 victory over fourth-tier Port Vale but Manchester United and Wolverhampton Wanderers face an unwanted replay after drawing 0-0 at Molineux on Saturday. Goals from Oleksandr Zinchenko, Sergio Aguero, Taylor Harwood-Bellis and Phil Foden made it a routine day for City, although Tom Pope had equalised for a Vale side sitting 74 places lower in the standings.
Brown Ideye scored twice as West Bromwich Albion progressed to the quarter-finals of the FA Cup.
Lexus continues its hybrid offensive in the country with the new NX midsize luxury SUV that eyes the popular Mercedes-Benz GLC and the Range Rover Evoque, among others
Liverpool surrendered a two-goal lead as they were held to a 2-2 draw by third-tier Shrewsbury Town in the FA Cup fourth round on Sunday after second-half substitute Jason Cummins struck twice to inject some much-needed late magic into the competition. Earlier, Harry Maguire's thunderbolt for Manchester United started a goal rush at Tranmere where the Reds scored five times before halftime. Diogo Dalot, Jesse Lingard, Phil Jones, Anthony Martial and Mason Greenwood also scored.
News of all that's transpired on and off the football field
Images from the League Cup matches played on Tuesday
Alan Pardew's dream of reprising a celebrated 25-year-old FA Cup triumph was scuppered by Liverpool as the seven-times champions came from behind to book a place in the quarter-finals with a 2-1 win at Crystal Palace on Saturday. This year's shock-laden competition had continued with second-tier Blackburn Rovers' 4-1 thrashing of the Premier League's Stoke City.
News of all that's transpired on and off the football field
Zlatan Ibrahimovic noted this week in his own inimitably self-regarding fashion that he had taken just three months to conquer England.
At an expected price tag of Rs 600,000 to Rs 900,000, it does spell trouble for the contenders in the sub-4-metre SUV space.
Chelsea demolished the team that succeeded them as Premier League winners when champions Leicester City succumbed tamely 3-0 at Stamford Bridge on Saturday.
With an amazing start some of more interesting models to be launched this month are - Mercedes Maybach S600, Renault KWID, new Ford Figo and the Mahindra TUV300( launched recently)
At Rs 470,000 for the base petrol variant, Tigor is now the cheapest compact sedan in the country
The Premier League kicked off in unique fashion on Saturday as an own goal by Tottenham Hotspur's Kyle Walker gave Manchester United a 1-0 victory in an undistinguished season opener at Old Trafford.
Sam Allardyce was sacked as England manager on Tuesday having behaved "inappropriately" when seeking a lucrative sideline role while talking to undercover reporters, bringing a crushing end to his dream job after one match and 67 days in charge.
A century-old European bicycle brand gets a makeover under its new Indian owner. But is there room for yet another premium commuter bike?
News of all that's transpired on and off the football field
News of all that's transpired on and off the football field
Audi India launched the second generation 2016 Audi R8 at the show.
The world champions now have 19 points while Poland, 8-1 winners over Gibraltar, are on 17.