William Donald Grigg (born 3 July 1991) is a professional footballer who plays as a striker for EFL League Two club Chesterfield.

[11][12][13] Having courted interest from West Bromwich Albion, Grigg signed a scholarship at League One side Walsall in the summer of 2008.

[14] Assigned the number 24 shirt, he made his league debut as an 89th-minute substitute for Dwayne Mattis in a 0–0 draw with Cheltenham Town on 20 December 2008.

[17] Grigg featured regularly as a second-half substitute during the 2010–11 season and made his first start for Walsall in a 1–0 FA Cup second round defeat at Torquay United on 27 November 2010.

[22] Grigg became a regular starter during the 2012–13 season and scored seven goals before the New Year, including a brace in a 4–2 away victory over Milton Keynes Dons on Boxing Day.

[24][25] His impressive form continued as he scored his first hat-trick in a 3–0 victory at Carlisle United on 26 February,[26] bringing his season tally up to 14 goals.

He finished the 2012–13 season with a run of 10 goals in 11 matches,[27] as Walsall mounted an unsuccessful challenge to qualify for the League One playoffs.

[35] Injury, international call ups and being played out of position by manager Uwe Rösler led to Grigg enduring a stuttering start to his Brentford career and he admitted suffering a dip in confidence.

[40] In March and still behind Clayton Donaldson and Marcello Trotta in the pecking order, Grigg told the Hounslow Chronicle "I haven't become a bad striker overnight.

[6][43] On 18 July 2014, it was announced that Grigg had joined League One side Milton Keynes Dons from Brentford on a season long loan.

[46] Grigg hit his next patch of regular goalscoring form in mid-March 2015, scoring nine goals in eight matches to help consolidate the Dons' third place in the table.

[46] On 14 July 2015, Grigg signed for newly relegated League One club Wigan Athletic on a three-year contract for an undisclosed fee,[43] reported to be "around £1 million".

[55] On 19 February 2018, Grigg scored the only goal in Wigan's 1–0 home win against Manchester City in the FA Cup fifth round.

[60] Grigg's goal put Sunderland 1–0 ahead of home side Bristol Rovers in the EFL Trophy semi final on 5 March.

[61] On 31 March Grigg started in the 2019 EFL Trophy Final against Portsmouth, he was substituted off in the 77th minute with Sunderland 1–0 up through an Aiden McGeady goal.

[68] On 14 July 2022, Grigg returned to League One club Milton Keynes Dons on a free transfer for a third spell, this time on a permanent basis.

[72][73] On 22 June 2023, Grigg joined National League club Chesterfield for an undisclosed fee on a 3-year contract, reuniting with previous manager Paul Cook.

He scored on his U21 debut after coming on as a substitute against San Marino in a UEFA U21 European Championship Qualifier[77] on 3 September 2010 and earned his first senior cap in a 6–0 defeat to the Netherlands in a friendly on 2 June 2012, playing the full 90 minutes.

[83] Grigg was born into an Aston Villa-supporting family and supported the club up until the age of seven, when he joined Birmingham City and changed his allegiances.