diff --git a/sinatra-contrib/lib/sinatra/capture.rb b/sinatra-contrib/lib/sinatra/capture.rb
index 0bbe7a17..10a00733 100644
--- a/sinatra-contrib/lib/sinatra/capture.rb
+++ b/sinatra-contrib/lib/sinatra/capture.rb
@@ -97,8 +97,7 @@ module Sinatra
         result = block[*args]
       elsif current_engine == :erb || current_engine == :slim
         @_out_buf, _buf_was = '', @_out_buf
-        block[*args]
-        result = eval('@_out_buf', block.binding)
+        result = block.call(*args)
         @_out_buf = _buf_was
       else
         buffer     = eval '_buf if defined?(_buf)', block.binding
diff --git a/sinatra-contrib/spec/content_for/parameter_value.erb b/sinatra-contrib/spec/content_for/parameter_value.erb
new file mode 100644
index 00000000..b22350c1
--- /dev/null
+++ b/sinatra-contrib/spec/content_for/parameter_value.erb
@@ -0,0 +1 @@
+<% content_for :foo, 'foo' %>
diff --git a/sinatra-contrib/spec/content_for/parameter_value.erubis b/sinatra-contrib/spec/content_for/parameter_value.erubis
new file mode 100644
index 00000000..b22350c1
--- /dev/null
+++ b/sinatra-contrib/spec/content_for/parameter_value.erubis
@@ -0,0 +1 @@
+<% content_for :foo, 'foo' %>
diff --git a/sinatra-contrib/spec/content_for/parameter_value.haml b/sinatra-contrib/spec/content_for/parameter_value.haml
new file mode 100644
index 00000000..6f492b28
--- /dev/null
+++ b/sinatra-contrib/spec/content_for/parameter_value.haml
@@ -0,0 +1 @@
+- content_for :foo, 'foo'
diff --git a/sinatra-contrib/spec/content_for/parameter_value.slim b/sinatra-contrib/spec/content_for/parameter_value.slim
new file mode 100644
index 00000000..6f492b28
--- /dev/null
+++ b/sinatra-contrib/spec/content_for/parameter_value.slim
@@ -0,0 +1 @@
+- content_for :foo, 'foo'
diff --git a/sinatra-contrib/spec/content_for_spec.rb b/sinatra-contrib/spec/content_for_spec.rb
index f53235d4..3cc28102 100644
--- a/sinatra-contrib/spec/content_for_spec.rb
+++ b/sinatra-contrib/spec/content_for_spec.rb
@@ -210,6 +210,11 @@ describe Sinatra::ContentFor do
             expect(body).to eq("bar")
           end
 
+          it 'renders content set as parameter' do
+            expect(get('/parameter_value')).to be_ok
+            expect(body).to eq("foo")
+          end
+
           it 'renders blocks declared with the same key you use when rendering' do
             expect(get('/same_key')).to be_ok
             expect(body).to eq("foo")