diff --git a/weasyprint/tests/test_layout.py b/weasyprint/tests/test_layout.py
index fe315592..5cbc3f59 100644
--- a/weasyprint/tests/test_layout.py
+++ b/weasyprint/tests/test_layout.py
@@ -738,7 +738,7 @@ def test_breaking_linebox():
     assert line3.children[0].children[0].text == 'c'
     assert line3.children[1].text == 'd'
 
-    # Regression test #1 for https://github.com/Kozea/WeasyPrint/issues/580
+    # Regression test for https://github.com/Kozea/WeasyPrint/issues/580
     page, = parse(
         '<div style="width: 5.5em; font-family: ahem">'
         '<span>aaaa aaaa a a a</span><span>bc</span>')
@@ -752,6 +752,17 @@ def test_breaking_linebox():
     assert line4.children[0].children[0].text == 'a'
     assert line4.children[1].children[0].text == 'bc'
 
+    # Regression test for https://github.com/Kozea/WeasyPrint/issues/586
+    page, = parse(
+        '<div style="width: 5.5em; font-family: ahem">'
+        'a a <span style="white-space: nowrap">/ccc</span>')
+    html, = page.children
+    body, = html.children
+    div, = body.children
+    line1, line2 = div.children
+    assert line1.children[0].text == 'a a'
+    assert line2.children[0].children[0].text == '/ccc'
+
 
 @assert_no_logs
 def test_linebox_text():
diff --git a/weasyprint/text.py b/weasyprint/text.py
index 6e8a7c97..6a65743b 100644
--- a/weasyprint/text.py
+++ b/weasyprint/text.py
@@ -1001,8 +1001,6 @@ def split_first_line(text, style, context, max_width, justification_spacing,
             if second_line is None and first_line_text:
                 # The next word fits in the first line, keep the layout
                 resume_at = len(new_first_line_text.encode('utf-8')) + 1
-                if resume_at == len(text.encode('utf-8')):
-                    resume_at = None
                 return first_line_metrics(
                     first_line, text, layout, resume_at, space_collapse, style)
             elif second_line: