Lapslie first joined Charlton Athletic in 2009 and quickly progressed through the youth ranks.[3] Lapslie appeared on the bench during Charlton's EFL Trophy tie against Colchester United in November 2016, however, he failed to feature in their 1–1 draw.[4] On 29 August 2017, Lapslie scored on his professional debut against Crawley Town in an EFL Trophy tie.[5]
Chelmsford City (loan)
On 2 February 2018, Lapslie signed for Chelmsford City on a one-month loan.[6] Lapslie returned to Charlton at the start of March having not made any appearances for Chelmsford.
Mansfield Town
On 15 October 2020, Lapslie joined Mansfield Town on a season-long loan.[7]
On 19 January 2021, Lapslie's loan move to Mansfield Town was made permanent for an undisclosed fee.[8]
On 4 December 2021, Lapslie scored two goals away at Doncaster Rovers to send Mansfield into the third round of the FA Cup as Mansfield knocked Doncaster out 3–2. [9]
Gillingham
On 14 January 2023, Lapslie signed for EFL League Two side Gillingham.[10] On 15 May 2024, the club put him on the transfer list.[11]