diff --git a/groestl.c b/groestl.c
index a0c986fbc3..260863e29f 100644
--- a/groestl.c
+++ b/groestl.c
@@ -3105,6 +3105,18 @@ groestl512_Final(void *cc, void *dst)
 	groestl_big_close((sph_groestl_big_context *)cc, 0, 0, dst, 64);
 }
 
+void
+groestl512_DoubleTrunc(void *cc, void *dst)
+{
+	char buf[64];
+
+	groestl512_Final(cc, buf);
+	groestl512_Init(cc);
+	groestl512_Update(cc, buf, sizeof(buf));
+	groestl512_Final(cc, buf);
+	memcpy(dst, buf, 32);
+}
+
 /* see sph_groestl.h */
 void
 sph_groestl512_addbits_and_close(void *cc, unsigned ub, unsigned n, void *dst)
diff --git a/groestl.h b/groestl.h
index 49506622d4..08263f3daa 100644
--- a/groestl.h
+++ b/groestl.h
@@ -302,6 +302,9 @@ void groestl512_Update(void *cc, const void *data, size_t len);
  */
 void groestl512_Final(void *cc, void *dst);
 
+
+void groestl512_DoubleTrunc(void *cc, void *dst);
+
 /**
  * Add a few additional bits (0 to 7) to the current computation, then
  * terminate it and output the result in the provided buffer, which must
diff --git a/hasher.c b/hasher.c
index 93881be611..b8d0b919ba 100644
--- a/hasher.c
+++ b/hasher.c
@@ -34,7 +34,7 @@ void hasher_Init(Hasher *hasher, HasherType type) {
 	case HASHER_BLAKED:
 		blake256_Init(&hasher->ctx.blake);
 		break;
-	case HASHER_GROESTL:
+	case HASHER_GROESTLD_TRUNC:
 		groestl512_Init(&hasher->ctx.groestl);
 		break;
 	}
@@ -54,7 +54,7 @@ void hasher_Update(Hasher *hasher, const uint8_t *data, size_t length) {
 	case HASHER_BLAKED:
 		blake256_Update(&hasher->ctx.blake, data, length);
 		break;
-	case HASHER_GROESTL:
+	case HASHER_GROESTLD_TRUNC:
 		groestl512_Update(&hasher->ctx.groestl, data, length);
 		break;
 	}
@@ -70,20 +70,18 @@ void hasher_Final(Hasher *hasher, uint8_t hash[HASHER_DIGEST_LENGTH]) {
 	case HASHER_BLAKED:
 		blake256_Final(&hasher->ctx.blake, hash);
 		break;
-	case HASHER_GROESTL:
-		groestl512_Final(&hasher->ctx.groestl, hash);
-		break;
+	case HASHER_GROESTLD_TRUNC:
+		groestl512_DoubleTrunc(&hasher->ctx.groestl, hash);
+		return;
 	}
 
 	switch (hasher->type) {
 	case HASHER_SHA2D:
 		hasher_Raw(HASHER_SHA2, hash, HASHER_DIGEST_LENGTH, hash);
 		break;
-
 	case HASHER_BLAKED:
 		hasher_Raw(HASHER_BLAKE, hash, HASHER_DIGEST_LENGTH, hash);
 		break;
-	
 	default:
 		break;
 	}
diff --git a/hasher.h b/hasher.h
index 4fa722f50e..673cf9fa79 100644
--- a/hasher.h
+++ b/hasher.h
@@ -39,7 +39,7 @@ typedef enum {
     HASHER_SHA2D,
     HASHER_BLAKED,
 
-    HASHER_GROESTL,
+    HASHER_GROESTLD_TRUNC, /* Double Groestl512 hasher truncated to 256 bits */
 } HasherType;
 
 typedef struct {