SAN DIEGO -- The past week and a half provided a useful litmus test for the Padres -- nine consecutive games against three National League West rivals, all of whom sit above .500.

It didn’t end the way the Padres hoped it would – a 7-1 loss to the Giants on Sunday afternoon at Petco Park. But after posting a 6-3 record against the Dodgers, D-backs and Giants, it would be difficult to consider that stretch anything but a success.

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The Padres won the first two games of their weekend set against the Giants but dropped the finale. Fernando Tatis Jr. hit a towering first-inning home run, but the Padres’ offense was otherwise unable to solve Giants right-hander Kevin Gausman, who didn’t allow another run across six innings.

The Padres sit three games over .500, yet they’re insistent they haven’t found their top gear this season.

“We’re doing OK, but I feel that we’ve got a ways to go to get to our ceiling,” said Padres manager Jayce Tingler. “Ultimately, I feel that’s a good thing.”

So how, exactly, do the Padres reach that ceiling. Here are three things they need:

1. Legitimate lineup depth
This was supposed to be a separator for the Padres this season. On paper, they built one of the deepest offenses in baseball, with a bottom of the order that didn’t offer much respite to opposing pitchers.

It hasn’t played out that way. Tommy Pham is hitting .205. Victor Caratini is hitting .215. Ha-Seong Kim is hitting .216. The Padres entered play Sunday with a .579 OPS in the 7-8-9 spots, not including pitchers, which ranks 14th out of 15 teams in the National League.

Every team in baseball has deficiencies at the bottom of their lineup. (That’s why those hitters aren’t hitting at the top.) But the Padres expected much more production than this.

Fortunately, there are signs that things are trending in the right direction. Most notably, catcher Austin Nola has returned from his four-week stint on the injured list with a fractured finger. He had a slash line of .273/.353/.472 last season and brings a different dimension offensively. Pham has also shown signs of a breakout. He’s 6-for-14 with a walk during that nine-game stretch against division rivals (and he’s absolutely scorched a couple baseballs).

2. A cleaner defensive game
Another game, another defensive blunder leading directly to runs. This time it was Joe Musgrove -- one of the better fielding pitchers in the sport -- who couldn’t handle a routine bunt in the top of the third inning. Musgrove ill-advisedly tried for an out at second, bobbled the ball, and didn’t have a play at first. The Giants then scored four runs in the frame.

It was the Padres’ 25th error this season, tied for the most in the Majors. There’s no reason that should be happening. The San Diego defense was one of the cleanest in baseball last season, and it returned starters at all eight defensive positions this year.

Of course, issues at shortstop are the driving force behind that error count. Tatis has 10 of them, the highest individual mark in baseball, despite missing 10 games while on the IL. Tatis was solid this weekend, and he made a pair of outstanding plays -- a diving stop Saturday night and a rangy snare with a throw from his knees on Sunday.

But it’ll take more than one clean weekend. Tatis -- like the Padres -- needs to do it consistently.

3. More length from their starters
Musgrove struggled Sunday, allowing six runs (five earned) across five innings. He gets a bit of a pass here, as one of only two Padres to complete six innings this season. Yu Darvish has done it five times, Musgrove three.

The Padres haven’t gotten nearly enough length out of their starting pitchers. On the season, the San Diego bullpen has been asked to cover 125 innings -- tied with the Rays for the most in the Majors. Expect that number to grow on Monday, when newly promoted right-hander Miguel Diaz takes the ball for the opener against Pittsburgh, as the Padres deal with a handful of injuries.

Those injuries, of course, have contributed to the heavy bullpen workload -- and the ’pen has generally handled those days expertly. Still, no matter how good the Padres’ relief corps has looked this season, if the Padres don’t get more length from their starters, that tax will come due.