diff --git a/proto/substrait/algebra.proto b/proto/substrait/algebra.proto
index 70f48648a..b716ac507 100644
--- a/proto/substrait/algebra.proto
+++ b/proto/substrait/algebra.proto
@@ -1187,20 +1187,19 @@ message Expression {
     }
 
     message IntervalDayToSecond {
+      reserved 3;
+      reserved "microseconds";
+
       int32 days = 1;
       int32 seconds = 2;
 
-      // Consumers should expect either (miroseconds) to be set or (precision and subseconds) to be set
-      oneof precision_mode {
-        int32 microseconds = 3 [deprecated = true]; // use precision and subseconds below, they cover and replace microseconds.
-        // Sub-second precision, 0 means the value given is in seconds, 3 is milliseconds, 6 microseconds, 9 is nanoseconds, 12 is picoseconds. Should be used with subseconds below.
-        int32 precision = 4;
-      }
+      // Sub-second precision, 0 means the value given is in seconds, 3 is milliseconds, 6 microseconds, 9 is nanoseconds, 12 is picoseconds. Should be used with subseconds below.
+      int32 precision = 4;
 
       // The sub-second component only, expressed as the number of 1e(-precision)
       // units (e.g. with precision 12 this is a number of picoseconds in the
       // range [0, 1e12)). Whole seconds belong in the seconds field above, not
-      // here. Should only be used with precision field, not microseconds.
+      // here. Should only be used with precision field.
       int64 subseconds = 5;
     }