This will be the fourth time both Johnny Cueto and Randy Wells will face each other's teams this season, but only the first time they have faced each other. Cueto shut down the Cubs back in April, blanking them over 7 innings, but in his other two starts since then he has been fairly pedestrian. He has pitched well in 4 career starts at Wrigley though, posting a 3.04 ERA while striking 19 batters in 26.2 innings. As you would expect with this team, he is just 1-3 in those starts.
The Cubs have won all three of Wells' previous starts against the Reds, in a large part because the Reds haven't managed to put up much offense against the rookie right-hander. Over 20 innings against Wells, the Reds have put just 24 runners on base, with only 6 of those runners crossing the plate. It's a fine microcosm of the Reds season as a whole.
The offense is batting just .191/ .278/.309 on this road trip, averaging a mere 2.8 runs per game. This is perhaps the worst offensive stretch of the season, coincidentally coming immediately after one of the best runs of the season. Nobody claimed the offense on this team wasn't streaky.