FA Cup Round-Up: Wigan shock West Ham

Wigan have slumped down English football's ladder since winning the FA Cup in 2013, but the League One leaders rekindled memories of that run to Wembley as they reached the last 16 at the expense of David Moyes's depleted Premier League side.

Northern Ireland striker Grigg made it five goals in as many Cup ties this season when he put Wigan ahead as early as the seventh minute with a towering header past England goalkeeper Joe Hart.

To make matters worse for the Hammers they were a man down four minutes into the second half when Arthur Masuaku was sent-off, having appeared to spit at Wigan's Nick Powell.

Grigg made it 2-0 from the penalty spot in the 62nd minute following Reece Burke's handball in the box.

"From start to finish we were the best side," Grigg told the BBC. "We had lots of energy played with a high tempo and thought our quality today was top draw."

Elsewhere struggling Premier League sides Swansea and Huddersfield played out 1-1 draws with lower-division Notts County and Birmingham City respectively, leading to unwanted replays for teams whose priority is remaining in the top flight.

The Swans, bottom of the Premier League, took the lead when Luciano Narsingh scored just his second goal in 31 games for the Welsh club on the stroke of half-time.

But fourth-tier County equalised in the 62nd minute through Jon Stead.

"We were disappointed to conceded the goal just before half time," said Stead. "But the response at the start of the second half was great and really we should have scored another goal early on."

It was a similar story when a much-changed Huddersfield side, indicating manager David Wagner's preference for Premier League survival over a Cup run, took an early lead against Birmingham through a Steve Mounie header.

Lukas Jutkiewicz, however, drew a Birmingham side battling to avoid relegation from the second-tier Championship level in the 54th minute.

Premier League Brighton were also on the verge of a replay until Glenn Murray's 90th-minute goal secured a 1-0 win over Championship side Middlesbrough.

- Diabate's debut double -

Saturday's early kick-off saw Fousseni Diabate score twice on his Leicester debut as the Premier League club won 5-1 at nearby East Midlands side Peterborough.

Any hopes third-tier Peterborough might create an upset lasted all of nine minutes, with Diabate's opening goal followed by two more from Kelechi Iheanacho that gave the Foxes a 3-0 lead at half-time.

Peterborough's Andrew Hughes pulled one back in the 58th minute before Diabate, who arrived at the King Power Stadium from French Ligue 2 club Gazelec Ajaccio earlier this month, scored his second and Leicester's fourth in the 87th minute. Wilfred Ndidi made it 5-1 in stoppage-time.

Nottingham Forest's FA Cup run ended just one round after they knocked out holders Arsenal courtesy of a 2-1 defeat by Championship rivals Hull.

The first of this weekend's all-Premier League ties saw Southampton beat Watford 1-0 as Jack Stephens marked his 24th birthday with a goal to ensure Javi Gracia's reign as Hornets manager started with a defeat.

Liverpool play West Brom at Anfield in the last of Saturday's ties.

Chelsea face Newcastle in another all top-flight clash on Sunday when league leaders Manchester City continue their bid for an unprecedented 'quadruple' of major trophies in the one season away to second-tier Cardiff.

Manchester United made it through to the fourth round on Friday, with new signing Alexis Sanchez impressing on debut in a 4-0 win away to lowly Yeovil Town.