diff --git a/src/expr.rs b/src/expr.rs
index a1fe1153e55..9aafd71dd22 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -1547,7 +1547,7 @@ pub fn span_ends_with_comma(context: &RewriteContext, span: Span) -> bool {
     for (kind, c) in CharClasses::new(context.snippet(span).chars()) {
         match c {
             _ if kind.is_comment() || c.is_whitespace() => continue,
-            ')' | '}' => result = result && prev_char != c,
+            ')' | '}' => result = result && prev_char != ')' && prev_char != '}',
             ',' => result = true,
             _ => result = false,
         }
diff --git a/src/matches.rs b/src/matches.rs
index 83ff70ea196..42f46608b52 100644
--- a/src/matches.rs
+++ b/src/matches.rs
@@ -13,8 +13,8 @@
 use std::iter::repeat;
 
 use config::lists::*;
-use syntax::{ast, ptr};
 use syntax::codemap::{BytePos, Span};
+use syntax::{ast, ptr};
 
 use codemap::SpanUtils;
 use comment::combine_strs_with_missing_comments;
diff --git a/tests/target/issue-2551.rs b/tests/target/issue-2551.rs
new file mode 100644
index 00000000000..d7b0d625b9e
--- /dev/null
+++ b/tests/target/issue-2551.rs
@@ -0,0 +1,3 @@
+mcro!(func(A {
+    a: 12345667800111111111111,
+}));