It takes an entire offseason to build expectations and just a week or two to shatter them. We all know it’s a long season, and most of the statistical noise washes out over 162 games. But no amount of equivocation dampens the shock of knowing that the Blue Jays, a team with designs on a playoff run, are 1–6, or that Rangers closer Sam Dyson has a 33.00 ERA and two blown saves in four appearances. The same goes for pleasant surprises — no matter how you look at it, Diamondbacks outfielder Jeremy Hazelbaker is actually hitting .857 right now.

But how much good baseball karma can you bank in 10 days, and how much panic is appropriate for a team that’s had a rough go of it? How long until the old adage, “You can’t win the pennant in April, but you can lose it,” starts to feel like a threat? Well, you can’t really throw away the season in the first 10 days, but you can do a lot of damage.

Pick a would-be contender that’s stumbled out of the gate — Toronto, Seattle, Texas — and right now, the record itself is scary. Most teams that start 2–5, like the Rangers have, miss the playoffs, because teams that start 2–5 tend not to be very good. Maybe that’s not true of these three clubs, since, injuries to players like Jean Segura and Drew Smyly aside, they’re still the same teams they were April 1. Starting 2–5 isn’t enough to kill any team’s playoff aspirations at any rate. Every team has a freakishly good or bad run at some point during the year, but when there’s nothing else on the team’s record to cushion the blow, it’s hard not to panic.

And I do mean every team. Last year’s Cubs went 4–8 from May 11 through May 23, which didn’t freak anyone out because when that run started they were already 25–6, and at no point during that slide did Chicago’s division lead drop below five games. Hell, the Cubs were under .500 for the entire month of July last year. Even the 2001 Mariners, who won a record-tying 116 games, had a 2–5 run in mid-June and a four-game losing streak in September.

While that line of thinking is comforting, it misses the real problem by running afoul of the gambler’s fallacy. Let’s say you were flipping a coin 100 times — before you began, you’d expect it to come up heads 50 times and tails 50 times. But if it came up heads the first five times, that doesn’t make it more likely to come up tails later, so as to end at 50–50. Each coin flip is still a 50–50 proposition going forward. In the same way, just because a team has an aberrant bad stretch to begin the season doesn’t mean it won’t have another one later on.

Baseball Prospectus calculates playoff odds by simulating the remaining schedule based on its PECOTA projection system. Every morning, the real-world standings and statistics get updated and the process is repeated. PECOTA was created by humans, so it’s not infallible, but BP’s playoff odds mix the results of the schedule thus far with how good we — or at least PECOTA — believe a particular team to be. Most usefully, it spits out specific probabilities, including adjusted playoff odds, or the percent chance a team will make the divisional round of the playoffs.

And so far, at least according to those odds, nobody’s totally nuked their season yet. All six division leaders in adjusted playoff odds on Opening Day still lead their divisions on the morning of April 12, and the top 10 teams in adjusted playoff odds 10 days ago — the Dodgers, Cubs, Indians, Astros, Mets, Red Sox, Nationals, Rays, Giants, and Mariners — are still the top 10 teams.

But the issue isn’t a division favorite playing its way out of contention in a week. The Blue Jays, Mariners, and Rangers are wild-card contenders, all with between a 20 percent and 35 percent chance of making the divisional round on Opening Day, and they’ve started 1–6, 2–7, and 2–5, respectively.

All three clubs have seen their adjusted playoff odds go down between 8.6 and 11.1 percentage points already. PECOTA projected before the season started that all of them would finish within a couple of games of .500, meaning they could absolutely make the playoffs if they got a few breaks. Starting 2–6 essentially burns up that margin for error.

Before the season, PECOTA had the Mariners as an 84–78 team. Over the past four years, it’s taken an average of 89 wins to get the second AL wild-card spot. That means the Mariners had five games to make up in terms of injury luck, run differential shenanigans, and PECOTA just flat-out undervaluing players like Segura, in order to make the postseason. That seemed doable. Now, PECOTA projects them to go 82–80, counting that 2–7 start, and Seattle has nine fewer games with which to make up the gap. They’re not sunk, but they’re taking on water.

BP has historical daily playoff odds dating back to 2013, and since then, only eight teams have dropped double digits in the season’s first 10 days, including this year’s Pirates, who have gone only 3–4, but have seen their adjusted playoff odds go down more than 10 points, thanks mostly to the Cubs’ 5–2 start.

2017 Mariners: down 11.1

2017 Pirates: down 10.7

2016 Mets: down 11.2

2015 Indians: down 12.1

2015 Mariners: down 11

2015 Giants: down 11.2

2014 Dodgers: down 12.0 (The Dodgers started the 2014 season in Australia on March 22, and thanks to the two games Down Under, plus a Sunday night game on March 30, they’d played three games by the time most of the rest of the league started. But they lost 12 percentage points from the normal Opening Day, March 31, through April 9.)

2013 Angels: down 10.9

You can’t really take yourself out of the race in the first 10 days of the season, but you can absolutely take yourself out of the race in the first 30.

One of the best examples of this happened last season, when the Houston Astros, fresh off a playoff appearance, with a young and improving core, started the season 3–7 and wrapped up April with a 7–17 record. The Astros finished 84–78, 11 games out of the AL West lead and five games out of the second wild-card spot. Over the final five months of the season, the Astros went 77–61, just a shade better than a 90-win pace. Eighty-nine wins would’ve been good enough for a wild-card spot.

The truism “A win in April counts the same as a win in September” is interesting in this context. It is true that a game counts the same in the standings no matter when it comes, but a baseball season isn’t a series of 162 discrete, unrelated events. Each game takes on a different meaning depending on its position on the schedule. Games in September have higher pennant leverage and are therefore more scrutinized. For instance, nobody outside of Houston cared much about that seven-win April for the Astros last year, but another seven-win month, Boston’s 7–20 September in 2011, is a legendary collapse that, insofar as it led to the ouster of Theo Epstein and Terry Francona, probably changed the course of baseball history.

Except, by season’s end April games are the dog that didn’t bark; how the end stage of the regular season unfolds, and who has anything at stake by then, is a function of what happens in the relative anonymity of the spring. Even leaving aside the effect of losing on morale — we might not be able to quantify it, but losing sucks, and even professional athletes can either press or check out completely when they get discouraged — a team’s position in the standings has a huge impact on what that team does at the trade deadline.

Again consider the Astros. In 2015, with his team in first place in late July, GM Jeff Luhnow traded for Scott Kazmir and Carlos Gomez to make a final push. (Both of those moves turned out to be disasters, but nobody knew that at the time.) The next year, with the Astros six games out at the deadline, Luhnow’s deadline activity was restricted to a pair of August 1 trades, swapping veteran pitchers Josh Fields and Scott Feldman for anonymous minor leaguers.

What about the flip side? Can a noncontender play its way into the playoffs in the season’s early days? Well, let’s look at the Astros again.

Houston went into the 2015 season with less than a 10 percent chance of making the divisional round, according to BP, and over the first 10 days of 2015, the Astros went 4–5, keeping their playoff odds more or less level. Then, in late April and early May, the Astros ripped off a 10-game winning streak that took their adjusted playoff odds from 14.1 percent to 44.4. That winning streak was exactly the margin by which the Astros had a winning record; they played a game under .500 the rest of the way, but made the postseason anyway.

Before Opening Day, PECOTA had the Arizona Diamondbacks penciled in for a 79–83 record, which isn’t some anomaly — Bovada set its win total over/under at 77.5. After 10 days, however, the Diamondbacks have the best record in baseball at 7–2. Just banking those wins is huge — even if the Diamondbacks revert to the .488 pace they were projected for, they’ll finish with 81 or 82 wins. How much more we can expect depends on what you think of their hot start.

Big jumps in adjusted playoff odds are a little more common; 10 teams since 2013 have gone up 10 percentage points or more in the season’s first 10 days, and the biggest mover, the 2015 Tigers, went up 17.6 points.

2017 Cubs: up 10.7

2016 White Sox: up 13.2

2016 Giants: up 12.8

2016 Nationals: up 13.3

2015 Tigers: up 17.6

2014 Brewers: up 11.4

2014 Giants: up 12.4

2013 Red Sox: up 10.7

2013 Rangers: up 16.7

2013 Braves: up 11.2

Those 10 teams falls into three groups: teams PECOTA undervalued (including two World Series champions), good teams that had great weeks, and bad teams that got hot early before crashing back down to earth.

The 2003 Royals are outside the scope of the data, but they’re as good an example of the latter group as exists in baseball history. In 2003, the Royals enjoyed their only winning season between 1995 and 2012, the age in which they were Oakland’s de facto Triple-A team.

Carlos Beltrán, a couple of decent veterans, and about 15 quad-A guys playing out of their minds started 16–3, an April hot streak that was every bit as much of a mirage as it seemed. That year’s AL Central was awful, with a 94-loss Indians team and the legendary 119-loss Tigers propping up the rest of the division. Kansas City went 10–1 against those two teams during that 16–3 run, 27–11 against them overall, and 56–68 against everyone else. The Royals finished 83–79 that year, and they weren’t even that good; they ended up with the run differential of a 78–84 team. If that Royals team can start 16–3, any hot start can turn out be an illusion.

Between the return of A.J. Pollock and a rotation full of pitchers poised for a bounceback, there was always upside in the Diamondbacks, but PECOTA still has the Dodgers winning the division more than 80 percent of the time, which seems fair. Even so, it’s encouraging that through two starts, Patrick Corbin, Robbie Ray, and Zack Greinke all have ERAs below 2.50, and that Pollock’s arm is still fully attached to his body — anyone who lived through last season knows neither of those things is to be taken for granted.

The Diamondbacks’ situation is essentially the reverse of where the Mariners, Blue Jays, and Rangers find themselves — none of those teams are better or worse than they were 10 days ago, at least as far as we can tell, but the circumstances around them have changed their path to the playoffs. And when those paths are as long as a baseball season, and determined by such slim margins, no deviation is fatal this early, but no deviation is trivial.