diff --git a/ts/src/sourcemapper/sourcemapper.ts b/ts/src/sourcemapper/sourcemapper.ts
index 000fc880..123abebd 100644
--- a/ts/src/sourcemapper/sourcemapper.ts
+++ b/ts/src/sourcemapper/sourcemapper.ts
@@ -212,13 +212,21 @@ export class SourceMapper {
       return location;
     }
 
-    const generatedPos = {line: location.line, column: location.column};
+    const generatedPos = {
+      line: location.line,
+      column: location.column,
+      bias: sourceMap.SourceMapConsumer.LEAST_UPPER_BOUND,
+    };
 
     // TODO: Determine how to remove the explicit cast here.
     const consumer: sourceMap.SourceMapConsumer =
       entry.mapConsumer as {} as sourceMap.SourceMapConsumer;
 
-    const pos = consumer.originalPositionFor(generatedPos);
+    let pos = consumer.originalPositionFor(generatedPos);
+    if (pos.source === null) {
+      generatedPos.bias = sourceMap.SourceMapConsumer.GREATEST_LOWER_BOUND;
+      pos = consumer.originalPositionFor(generatedPos);
+    }
     if (pos.source === null) {
       return location;
     }