diff --git a/docs/changelog/120538.yaml b/docs/changelog/120538.yaml
new file mode 100644
index 0000000000000..dfd7e33f4be29
--- /dev/null
+++ b/docs/changelog/120538.yaml
@@ -0,0 +1,5 @@
+pr: 120538
+summary: "Revert unwanted ES|QL lexer changes from PR #120354"
+area: ES|QL
+type: bug
+issues: []
diff --git a/x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.tokens b/x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.tokens
index b1a16987dd8ce..366b455f16402 100644
--- a/x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.tokens
+++ b/x-pack/plugin/esql/src/main/antlr/EsqlBaseLexer.tokens
@@ -66,66 +66,68 @@ MINUS=65
 ASTERISK=66
 SLASH=67
 PERCENT=68
-NAMED_OR_POSITIONAL_PARAM=69
-OPENING_BRACKET=70
-CLOSING_BRACKET=71
-UNQUOTED_IDENTIFIER=72
-QUOTED_IDENTIFIER=73
-EXPR_LINE_COMMENT=74
-EXPR_MULTILINE_COMMENT=75
-EXPR_WS=76
-EXPLAIN_WS=77
-EXPLAIN_LINE_COMMENT=78
-EXPLAIN_MULTILINE_COMMENT=79
-METADATA=80
-UNQUOTED_SOURCE=81
-FROM_LINE_COMMENT=82
-FROM_MULTILINE_COMMENT=83
-FROM_WS=84
-ID_PATTERN=85
-PROJECT_LINE_COMMENT=86
-PROJECT_MULTILINE_COMMENT=87
-PROJECT_WS=88
-AS=89
-RENAME_LINE_COMMENT=90
-RENAME_MULTILINE_COMMENT=91
-RENAME_WS=92
-ON=93
-WITH=94
-ENRICH_POLICY_NAME=95
-ENRICH_LINE_COMMENT=96
-ENRICH_MULTILINE_COMMENT=97
-ENRICH_WS=98
-ENRICH_FIELD_LINE_COMMENT=99
-ENRICH_FIELD_MULTILINE_COMMENT=100
-ENRICH_FIELD_WS=101
-MVEXPAND_LINE_COMMENT=102
-MVEXPAND_MULTILINE_COMMENT=103
-MVEXPAND_WS=104
-INFO=105
-SHOW_LINE_COMMENT=106
-SHOW_MULTILINE_COMMENT=107
-SHOW_WS=108
-SETTING=109
-SETTING_LINE_COMMENT=110
-SETTTING_MULTILINE_COMMENT=111
-SETTING_WS=112
-LOOKUP_LINE_COMMENT=113
-LOOKUP_MULTILINE_COMMENT=114
-LOOKUP_WS=115
-LOOKUP_FIELD_LINE_COMMENT=116
-LOOKUP_FIELD_MULTILINE_COMMENT=117
-LOOKUP_FIELD_WS=118
-USING=119
-JOIN_LINE_COMMENT=120
-JOIN_MULTILINE_COMMENT=121
-JOIN_WS=122
-METRICS_LINE_COMMENT=123
-METRICS_MULTILINE_COMMENT=124
-METRICS_WS=125
-CLOSING_METRICS_LINE_COMMENT=126
-CLOSING_METRICS_MULTILINE_COMMENT=127
-CLOSING_METRICS_WS=128
+LEFT_BRACES=69
+RIGHT_BRACES=70
+NAMED_OR_POSITIONAL_PARAM=71
+OPENING_BRACKET=72
+CLOSING_BRACKET=73
+UNQUOTED_IDENTIFIER=74
+QUOTED_IDENTIFIER=75
+EXPR_LINE_COMMENT=76
+EXPR_MULTILINE_COMMENT=77
+EXPR_WS=78
+EXPLAIN_WS=79
+EXPLAIN_LINE_COMMENT=80
+EXPLAIN_MULTILINE_COMMENT=81
+METADATA=82
+UNQUOTED_SOURCE=83
+FROM_LINE_COMMENT=84
+FROM_MULTILINE_COMMENT=85
+FROM_WS=86
+ID_PATTERN=87
+PROJECT_LINE_COMMENT=88
+PROJECT_MULTILINE_COMMENT=89
+PROJECT_WS=90
+AS=91
+RENAME_LINE_COMMENT=92
+RENAME_MULTILINE_COMMENT=93
+RENAME_WS=94
+ON=95
+WITH=96
+ENRICH_POLICY_NAME=97
+ENRICH_LINE_COMMENT=98
+ENRICH_MULTILINE_COMMENT=99
+ENRICH_WS=100
+ENRICH_FIELD_LINE_COMMENT=101
+ENRICH_FIELD_MULTILINE_COMMENT=102
+ENRICH_FIELD_WS=103
+MVEXPAND_LINE_COMMENT=104
+MVEXPAND_MULTILINE_COMMENT=105
+MVEXPAND_WS=106
+INFO=107
+SHOW_LINE_COMMENT=108
+SHOW_MULTILINE_COMMENT=109
+SHOW_WS=110
+SETTING=111
+SETTING_LINE_COMMENT=112
+SETTTING_MULTILINE_COMMENT=113
+SETTING_WS=114
+LOOKUP_LINE_COMMENT=115
+LOOKUP_MULTILINE_COMMENT=116
+LOOKUP_WS=117
+LOOKUP_FIELD_LINE_COMMENT=118
+LOOKUP_FIELD_MULTILINE_COMMENT=119
+LOOKUP_FIELD_WS=120
+USING=121
+JOIN_LINE_COMMENT=122
+JOIN_MULTILINE_COMMENT=123
+JOIN_WS=124
+METRICS_LINE_COMMENT=125
+METRICS_MULTILINE_COMMENT=126
+METRICS_WS=127
+CLOSING_METRICS_LINE_COMMENT=128
+CLOSING_METRICS_MULTILINE_COMMENT=129
+CLOSING_METRICS_WS=130
 'dissect'=1
 'drop'=2
 'enrich'=3
@@ -179,10 +181,10 @@ CLOSING_METRICS_WS=128
 '*'=66
 '/'=67
 '%'=68
-']'=71
-'metadata'=80
-'as'=89
-'on'=93
-'with'=94
-'info'=105
-'USING'=119
+']'=73
+'metadata'=82
+'as'=91
+'on'=95
+'with'=96
+'info'=107
+'USING'=121