Arrieta has allowed only one base runner, a fifth-inning walk to Mike Napoli, while striking out nine Red Sox batters and throwing 103 pitches through seven frames.
The 28-year-old Arrieta is quietly having a tremendous season in Chicago, posting a 2.05 ERA and 2.10 FIP coming into Monday's outing. Arrieta had struck out 64 batters, while walking just 15 in 57 innings pitched.
Moreover, Arrieta had flirted with a no-hit bid in his last start. The right-hander retired the first 18 batters he faced in his last outing against the Reds on June 24 before allowing three hits over seven innings of work.
In five June starts prior to Monday, Arrieta had given up just four earned runs in 31⅔ innings.
If Arrieta were to no-hit the Red Sox, it would be the fourth no-hitter this season in Major League Baseball. Tim Lincecum no-hit the Padres last Wednesday, and prior to that, Dodgers teammates Josh Beckett and Clayton Kershaw held the Phillies and Rockies hitless, respectively.