diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 7a08b92..a8370d6 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -1161,7 +1161,11 @@ DecodeDateTime(char **field, int *ftype, int nf,
 						if (dterr < 0)
 							return dterr;
 					}
-					else if (flen > 4)
+					/*
+					 * should call DecodeNumberField only when anyone Date or
+					 * Time field is not yet found.
+					 */
+					else if (flen > 4 && (!(fmask & DTK_DATE_M) || !(fmask & DTK_TIME_M)))
 					{
 						dterr = DecodeNumberField(flen, field[i], fmask,
 												  &tmask, tm,