That marks the first time since April 14-15 (Odrisamer Despaigne and Brandon Morrow) -- and only the third time this season -- that Padres starters have worked seven innings in back-to-back starts.
Against the Cubs on Tuesday, Shields yielded two runs on a pair of homers in his seven-inning outing. He allowed six hits and a walk.
Ross allowed Chicago three runs on four hits and three walks in seven innings on Wednesday.
Shields had 11 strikeouts, his second-highest total of the season and the 25th double-digit strikeout game of his career. Ross had eight strikeouts. Padres starters entered Thursday with a National League-high 247 strikeouts on the season.
However, the Padres have yet to go through a full turn of the rotation without at least one starter having a subpar game.
In Thursday's rubber game against the Cubs -- the finale of a seven-game homestand -- Despaigne will be hoping for a reversal of recent form. The Cuban right-hander has allowed 15 runs on 20 hits and three walks in his last eight innings spanning two starts.
Two other notes on Shields and Ross:
• The two homers allowed by Shields on Tuesday raised his total on the season to 14 allowed in 55 1/3 innings, or 2.78 homers per nine innings. All but two of the homers were solo shots, and the other two were two-run homers. Shields leads the Major Leagues in home runs allowed.
• Ross has issued 29 walks in 52 2/3 innings this season; last season, he allowed 3.3 walks per nine innings.
FROM THE SCOREBOOK
• Left fielder Justin Upton's 11th homer run of the season on Wednesday was his ninth at Petco Park in 2015. He has a Major League-leading 22 RBIs at home this season. The Padres' single-season record for home runs at Petco Park is 15, set by Will Venable in 2013. Upton's homer on Wednesday tied him with Adrian Gonzalez (2008), Scott Hairston ('08) and Venable ('13) for the most home runs in Petco Park history before the All-Star break. Upton is hitting .350 (28-for-80) with a .398 on-base percentage and a .738 slugging percentage at Petco Park this season.
• Catcher Derek Norris is hitting .432 (16-for-37) with runners in scoring position this season and .438 (14-for-32) against left-handed pitching. He ranks fourth in the National League in batting vs. lefties and sixth with runners in scoring position. Norris also has 15 doubles just over one-fourth of the way into the season. The Padres record for most doubles in a season is 49 by Tony Gwynn in 1997. Norris ranks third in the Major League in doubles. Plus, he caught his 14th attempted basestealer on Wednesday night -- a total that both leads the Major Leagues and is six more than his previous career high.
• Right-handed reliever Brandon Maurer worked a scoreless inning against the Cubs on Wednesday. He has pitched 10 straight scoreless innings over his last nine outings since May 2. The scoreless-innings streak is the longest by a Padres starter or reliever this season. During the streak, Maurer has allowed four hits and two walks with seven strikeouts while halving his ERA from 4.50 to 2.25. Opponents have hit .121 against Maurer during the streak.
• Third baseman Will Middlebrooks was 2-for-4 on Wednesday night with his fourth double of the season and is 7-for-23 with a home run and a double in six starts since May 12. Before that, Middlebrooks was hitless in his previous 10 games (0-for-19) and in a 2-for-32 drought.