diff --git a/go/vt/vtgate/engine/route.go b/go/vt/vtgate/engine/route.go
index a3a862264df..9fff1e5afeb 100644
--- a/go/vt/vtgate/engine/route.go
+++ b/go/vt/vtgate/engine/route.go
@@ -23,7 +23,6 @@ import (
 	"strconv"
 	"time"
 
-	"vitess.io/vitess/go/jsonutil"
 	"vitess.io/vitess/go/mysql"
 	"vitess.io/vitess/go/sqltypes"
 	"vitess.io/vitess/go/stats"
@@ -128,41 +127,6 @@ func (obp OrderbyParams) String() string {
 	return val
 }
 
-// MarshalJSON serializes the Route into a JSON representation.
-// It's used for testing and diagnostics.
-func (route *Route) MarshalJSON() ([]byte, error) {
-	var vindexName string
-	if route.Vindex != nil {
-		vindexName = route.Vindex.String()
-	}
-	marshalRoute := struct {
-		Opcode                  RouteOpcode
-		Keyspace                *vindexes.Keyspace   `json:",omitempty"`
-		Query                   string               `json:",omitempty"`
-		FieldQuery              string               `json:",omitempty"`
-		Vindex                  string               `json:",omitempty"`
-		Values                  []sqltypes.PlanValue `json:",omitempty"`
-		OrderBy                 []OrderbyParams      `json:",omitempty"`
-		TruncateColumnCount     int                  `json:",omitempty"`
-		QueryTimeout            int                  `json:",omitempty"`
-		ScatterErrorsAsWarnings bool                 `json:",omitempty"`
-		Table                   string               `json:",omitempty"`
-	}{
-		Opcode:                  route.Opcode,
-		Keyspace:                route.Keyspace,
-		Query:                   route.Query,
-		FieldQuery:              route.FieldQuery,
-		Vindex:                  vindexName,
-		Values:                  route.Values,
-		OrderBy:                 route.OrderBy,
-		TruncateColumnCount:     route.TruncateColumnCount,
-		QueryTimeout:            route.QueryTimeout,
-		ScatterErrorsAsWarnings: route.ScatterErrorsAsWarnings,
-		Table:                   route.TableName,
-	}
-	return jsonutil.MarshalNoEscape(marshalRoute)
-}
-
 // RouteOpcode is a number representing the opcode
 // for the Route primitve. Adding new opcodes here
 // will require review of the join code and
diff --git a/go/vt/vtgate/engine/send.go b/go/vt/vtgate/engine/send.go
index 1f3db920045..50ca90fe829 100644
--- a/go/vt/vtgate/engine/send.go
+++ b/go/vt/vtgate/engine/send.go
@@ -17,8 +17,6 @@ limitations under the License.
 package engine
 
 import (
-	"encoding/json"
-
 	"vitess.io/vitess/go/sqltypes"
 	"vitess.io/vitess/go/vt/key"
 	"vitess.io/vitess/go/vt/proto/query"
@@ -53,26 +51,6 @@ func (s *Send) NeedsTransaction() bool {
 	return s.IsDML
 }
 
-// MarshalJSON serializes the Send into a JSON representation.
-// It's used for testing and diagnostics.
-func (s *Send) MarshalJSON() ([]byte, error) {
-	marshalSend := struct {
-		Opcode            string
-		Keyspace          *vindexes.Keyspace
-		TargetDestination key.Destination
-		Query             string
-		IsDML             bool
-	}{
-		Opcode:            "Send",
-		Keyspace:          s.Keyspace,
-		TargetDestination: s.TargetDestination,
-		IsDML:             s.IsDML,
-		Query:             s.Query,
-	}
-
-	return json.Marshal(marshalSend)
-}
-
 // RouteType implements Primitive interface
 func (s *Send) RouteType() string {
 	if s.IsDML {
diff --git a/go/vt/vtgate/engine/update_target.go b/go/vt/vtgate/engine/update_target.go
index bb782627d9f..f297c43e941 100644
--- a/go/vt/vtgate/engine/update_target.go
+++ b/go/vt/vtgate/engine/update_target.go
@@ -17,8 +17,6 @@ limitations under the License.
 package engine
 
 import (
-	"encoding/json"
-
 	vtrpcpb "vitess.io/vitess/go/vt/proto/vtrpc"
 	"vitess.io/vitess/go/vt/vterrors"
 
@@ -45,19 +43,6 @@ func (updTarget *UpdateTarget) description() PrimitiveDescription {
 	}
 }
 
-// MarshalJSON serializes the UpdateTarget into a JSON representation.
-// It's used for testing and diagnostics.
-func (updTarget *UpdateTarget) MarshalJSON() ([]byte, error) {
-	marshalUpdateTarget := struct {
-		Opcode string
-		Target string
-	}{
-		Opcode: "UpdateTarget",
-		Target: updTarget.Target,
-	}
-	return json.Marshal(marshalUpdateTarget)
-}
-
 // RouteType implements the Primitive interface
 func (updTarget UpdateTarget) RouteType() string {
 	return "UpdateTarget"
diff --git a/go/vt/vtgate/engine/vindex_func.go b/go/vt/vtgate/engine/vindex_func.go
index 5579f72a864..0e4e516c3b8 100644
--- a/go/vt/vtgate/engine/vindex_func.go
+++ b/go/vt/vtgate/engine/vindex_func.go
@@ -47,25 +47,6 @@ type VindexFunc struct {
 	noTxNeeded
 }
 
-// MarshalJSON serializes the VindexFunc into a JSON representation.
-// It's used for testing and diagnostics.
-func (vf *VindexFunc) MarshalJSON() ([]byte, error) {
-	v := struct {
-		Opcode VindexOpcode
-		Fields []*querypb.Field
-		Cols   []int
-		Vindex string
-		Value  sqltypes.PlanValue
-	}{
-		Opcode: vf.Opcode,
-		Fields: vf.Fields,
-		Cols:   vf.Cols,
-		Vindex: vf.Vindex.String(),
-		Value:  vf.Value,
-	}
-	return json.Marshal(v)
-}
-
 // VindexOpcode is the opcode for a VindexFunc.
 type VindexOpcode int