diff --git a/lib/Conversion/TorchOnnxToTorch/DefaultDomainAtoF.cpp b/lib/Conversion/TorchOnnxToTorch/DefaultDomainAtoF.cpp
index 61bea1d86..3d2cf8aae 100644
--- a/lib/Conversion/TorchOnnxToTorch/DefaultDomainAtoF.cpp
+++ b/lib/Conversion/TorchOnnxToTorch/DefaultDomainAtoF.cpp
@@ -377,7 +377,7 @@ void mlir::torch::onnx_c::populateDefaultDomainAtoF(
         return success();
       });
   patterns.onOp(
-      "Cast", 19, [](OpBinder binder, ConversionPatternRewriter &rewriter) {
+      "Cast", 1, [](OpBinder binder, ConversionPatternRewriter &rewriter) {
         Torch::ValueTensorType resultType;
         Value operand;
         int64_t dtypeIntOnnx, dtypeIntTorch;
@@ -848,7 +848,7 @@ void mlir::torch::onnx_c::populateDefaultDomainAtoF(
                       binder.op, resultType, lhs, rhs);
                   return success();
                 });
-  patterns.onOp("Equal", 19,
+  patterns.onOp("Equal", 1,
                 [](OpBinder binder, ConversionPatternRewriter &rewriter) {
                   Torch::ValueTensorType resultType;
                   Value lhs, rhs;
diff --git a/lib/Conversion/TorchOnnxToTorch/DefaultDomainGtoP.cpp b/lib/Conversion/TorchOnnxToTorch/DefaultDomainGtoP.cpp
index 710c9823f..e7544d6c1 100644
--- a/lib/Conversion/TorchOnnxToTorch/DefaultDomainGtoP.cpp
+++ b/lib/Conversion/TorchOnnxToTorch/DefaultDomainGtoP.cpp
@@ -169,7 +169,7 @@ void mlir::torch::onnx_c::populateDefaultDomainGtoP(
         return success();
       });
   patterns.onOp(
-      "Gemm", 13, [](OpBinder binder, ConversionPatternRewriter &rewriter) {
+      "Gemm", 1, [](OpBinder binder, ConversionPatternRewriter &rewriter) {
         Torch::ValueTensorType resultType;
         Value a, b, c;
         float alpha, beta;
@@ -313,7 +313,7 @@ void mlir::torch::onnx_c::populateDefaultDomainGtoP(
         }
         return failure();
       });
-  patterns.onOp("LeakyRelu", 16,
+  patterns.onOp("LeakyRelu", 1,
                 [](OpBinder binder, ConversionPatternRewriter &rewriter) {
                   Torch::ValueTensorType resultType;
                   Value operand;
diff --git a/test/Conversion/TorchOnnxToTorch/unsupported_fb_opt_ops.mlir b/test/Conversion/TorchOnnxToTorch/unsupported_fb_opt_ops.mlir
new file mode 100644
index 000000000..8401c378b
--- /dev/null
+++ b/test/Conversion/TorchOnnxToTorch/unsupported_fb_opt_ops.mlir
@@ -0,0 +1,40 @@
+// RUN: torch-mlir-opt <%s -split-input-file -verify-diagnostics -convert-torch-onnx-to-torch
+// FB OPT OPS from https://github.com/llvm/torch-mlir/issues/2689
+
+// -----
+// Fixed unecessarily high since-opset value
+func.func @cast_operation(%arg0: !torch.vtensor<[?,?,?,?],si64>) -> !torch.vtensor<[?,?,?,?],f32> attributes {torch.onnx_meta.ir_version = 9 : si64, torch.onnx_meta.opset_version = 18 : si64, torch.onnx_meta.producer_name = "backend-test", torch.onnx_meta.producer_version = ""} {
+  %208 = torch.operator "onnx.Cast"(%arg0) {
+    torch.onnx.to = 1 : si64
+  } : (!torch.vtensor<[?,?,?,?],si64>) -> !torch.vtensor<[?,?,?,?],f32>
+  return %208 : !torch.vtensor<[?,?,?,?],f32>
+}
+
+// -----
+func.func @div_operation(%arg0: !torch.vtensor<[1,64,768],f32>, 
+                          %arg1: !torch.vtensor<[1,64,1],f32>) 
+                          -> !torch.vtensor<[1,64,768],f32> attributes {torch.onnx_meta.ir_version = 9 : si64, torch.onnx_meta.opset_version = 18 : si64, torch.onnx_meta.producer_name = "backend-test", torch.onnx_meta.producer_version = ""} {
+  %209 = torch.operator "onnx.Div"(%arg0, %arg1) : (!torch.vtensor<[1,64,768],f32>, !torch.vtensor<[1,64,1],f32>) -> !torch.vtensor<[1,64,768],f32>
+  return %209 : !torch.vtensor<[1,64,768],f32>
+}
+
+// -----
+// Fixed.
+// this is the onnx opset 1 version of Equal, only int types.
+// this used to fail to legalize because the "since" value is set unecessarily high (19)
+func.func @equal_operation(%arg0: !torch.vtensor<[4],si64>, 
+                            %arg1: !torch.vtensor<[4],si64>) 
+                            -> !torch.vtensor<[4],i1> attributes {torch.onnx_meta.ir_version = 9 : si64, torch.onnx_meta.opset_version = 1 : si64, torch.onnx_meta.producer_name = "backend-test", torch.onnx_meta.producer_version = ""} {
+  %205 = torch.operator "onnx.Equal"(%arg0, %arg1) : (!torch.vtensor<[4],si64>, !torch.vtensor<[4],si64>) -> !torch.vtensor<[4],i1>
+  return %205 : !torch.vtensor<[4],i1>
+}
+
+
+// -----
+func.func @reduce_mean_operation(%arg0: !torch.vtensor<[1,64,768],f32>)
+                                 -> !torch.vtensor<[1,64,1],f32> attributes {torch.onnx_meta.ir_version = 9 : si64, torch.onnx_meta.opset_version = 18 : si64, torch.onnx_meta.producer_name = "backend-test", torch.onnx_meta.producer_version = ""} {
+  // The ReduceMean operation as provided.
+  // expected-error @+1 {{failed to legalize operation 'torch.operator'}}
+  %211 = torch.operator "onnx.ReduceMean"(%arg0) {torch.onnx.axes = [-1 : si64]} : (!torch.vtensor<[1,64,768],f32>) -> !torch.vtensor<[1,64,1],f32>
+  return %211 : !torch.vtensor<[1,64,1],f32>
+}
\ No newline at end of file