The Cubs’ Anthony Rizzo is batting .272 with 10 home runs and 28 RBI. (AP Photo/Charles Rex Arbogast)

The Chicago Cubs are off to a sizzling start after a 8-7 victory over the San Diego Padres on Tuesday night extended their winning streak to eight games. At 25-6, the Cubs have the best record in the major leagues, but that doesn’t stop General Manager Theo Epstein from preparing for the inevitable fall.

We almost throw out everything that has happened so far,” Epstein said. “We are on such a roll that we probably spend more time looking ahead to the inevitable challenging periods when we’re shorthanded and strapped, and things aren’t breaking our way. (We’re) trying to get ahead and figure out how we’re going to deal with that adversity.”

To see if a team is getting more bounces than usual, one needs to look no further than batting average on balls in play. The logic being defense, luck, and talent level all come into play at varying degrees, most of which are out of the batter’s control once the ball leaves the bat. However, the Cubs BABIP is just slightly above average (.297) at .309, so we shouldn’t see their hitting dry up overnight. In fact, their discipline and power at the plate indicate the opposite.

Chicago leads the majors in walk rate (12.8 percent) while striking out 19 percent of the time (fifth lowest in MLB). Ben Zobrist gets a free pass to first base in 17.3 percent of plate appearances, while Dexter Fowler (16.8 percent) and Anthony Rizzo (16.2 percent) round out the top-10 hitters in the league. Addison Russell (14.6 percent) finds himself in the top 20. If the Cubs can maintain their .370 on-base percentage for the entire season, they would rank as the third highest in baseball since the 1973 season, only a few ticks behind the 1994 New York Yankees and 1999 Cleveland Indians.

Getting on base is important, but so is scoring runs. Entering Wednesday’s games, the Cubs sport a run differential of 103 — 56 runs more than the next best team, the St. Louis Cardinals.

The Cubs became the fastest team in MLB history to reach plus-100 run differential (29 games) and are outscoring opponents by an average of 3.3 runs per game. And this too, appears sustainable. According to BaseRuns, which strips out the sequencing of events to estimate a team’s true-talent level, the Cubs should be winning 78.1 percent of their games. The next best team, the New York Mets (.654), is far behind.

The Cubs’ young slugger, Kris Bryant, is batting .295 with five home runs and 22 RBI, producing runs at a rate that is 34 percent higher than the league average (134 wRC+) after factoring in the league and park he plays in. Perhaps more encouraging is Bryant focusing on a flatter swing plane.

I committed to making a swing-thought change to be more flat with my swing,” Bryant told Carrie Muskat of “Last year, I was worse in terms of fouling pitches off. I told myself I didn’t want to do that and I wanted to hit the pitches in the strike zone.”

The launch angle is the angle of the ball as it comes off the bat. According to Statcast, the launch angle of Bryant’s hits in 2015 averaged 19.2 degrees. This year that average is down to 15.4 degrees. It’s a subtle difference, but an important one because launch angle, more so than exit velocity, is what leads to extra-base hits. So far this season Bryant has a .500 slugging percentage, up from .488 during his rookie year.

The Cubs are even doing damage on the base paths. According to FanGraphs’ all-encompassing base-running statistic, the team has produced 9.7 runs through stolen bases, taking extra bases, and by avoiding being thrown out on the bases. They are also the best fielding team, saving 21.3 runs with their gloves.

On the mound, Jake Arrieta is the ace of the staff. He is 6-0 with 44 strikeouts in 48 innings and a 1.13 ERA, which includes his no-hitter against the Reds earlier this year. Behind him is Jon Lester, John Lackey and Jason Hammel, who combine to produce 4.7 wins above replacement — the third best mark in the majors among qualified starters. Their bullpen is striking out 10.5 batters per nine innings and is inducing the highest rate of groundballs in the league (54.7 percent).

With a team so well balanced, it’s no surprise they are projected to win 102 games this year, nine more than the New York Mets and 11 more than the Boston Red Sox. The Cubs’ odds to win the World Series are also the highest in baseball at 19.7 percent. Perhaps that seems low, but consider there have been 41 teams since 1973 to win 100 game or more. Only eight (19.5 percent) have won a championship. Just one of those, the 2009 New York Yankees, occurred in this millennium.

“When it happens to us and we haven’t earned (anything) yet, it does get a little uncomfortable,” Epstein said. “You would rather go in a vacuum and earn it. That’s not the reality. It’s nobody’s fault. But hopefully at the end of the year we’ll look up and say, ‘Hey, we earned what people were saying about us.’ “