The　formation　of　metallic　glass　through　melt　processing　proves　to　be　the　most　challenging　for　pure　monatomic　face-centered　cubic　(FCC)　metals.　Though　it　has　long　been　conjectured　that　amorphous　monatomic　metals　can　be　generated　through　deforming　a　solid　at　room　temperature,　there　is　rarely　direct　evidence　to　prove　that　is　indeed　the　case.　In　this　study,　mechanical　loading　was　applied　to　nanometer-sized　crystals　inside　an　aberration-corrected　transmission　electron　microscopy,　and　atomic-scale　in　situ　evidence　is　provided　of　strain-induced　amorphization　in　Pt　and　Ni　near　room　tempera　-ture.　The　loading　was　applied　in　such　a　way　that　the　stress　state　is　complicated,　and　the　strain　distri-bution　is　non-uniform,　restricting　dislocation　activities　in　accommodating　the　imposed　strain.　The　local　lattice　distortion　is　then　rendered　so　large　and　the　associated　strain　energy　is　so　high　that　the　crys-tal　collapses　into　the　amorphous　state.　As　such,　even　elemental　FCC　metals　can　be　forced　to　become　amorphous.(c)　2022　Acta　Materialia　Inc.　Published　by　Elsevier　Ltd.　All　rights　reserved.