The Mariners are flying high, having won five straight after completing a four-game sweep of the Detroit Tigers on Thursday night to get over .500 for the first time in 2017. Here are three things to keep in mind this weekend as they battle the best team in baseball, the Houston Astros, for three games at Safeco Field.

1. A lineup with length is a good lineup indeed.

A funny thing happened when Jean Segura returned from the disabled list on Wednesday – the Mariners suddenly had their true intended lineup for the first time since he suffered his first injury during Seattle’s initial homestand. But whereas the team struggled offensively out of the gates in April, this lineup looks as long and formidable as any in baseball right now. There are no holes to be seen – not at the top, not in the middle, and certainly not at the bottom, where Mike Zunino will be sandwiched at No. 8 between either Mitch Haniger or Ben Gamel and Guillermo Heredia or Jarrod Dyson. It’s what GM Jerry Dipoto and manager Scott Servais envisioned as the team came together in the offseason, and for once in this season marked by tremendous bad luck, it actually is coming together. Segura, Robinson Cano and Nelson Cruz are playing like All-Stars. Gamel and Haniger are both Rookie of the Year candidates. Danny Valencia is playing to the level that the Mariners expected when they acquired him, Kyle Seager is coming alive, and Zunino appears to finally have found his groove at the big-league level. Then at No. 9 is either Heredia or Dyson, who each give Seattle excellent defense in center field, speed on the base paths and a pretty good bat for the last spot on a daily basis. Hard to find issue with that.

2. This Ben Gamel guy.

Another funny thing happened when Segura returned from the disabled list – there was a legitimate question as to whether he should return to the leadoff spot. OK, Servais made it pretty clear when talking to the media on Wednesday that he personally didn’t think too much about it, but considering Gamel had built the American League’s longest active hitting streak while hitting first in Segura’s absence, you can see why he could have. Two games later, that streak is still alive for Gamel at 14, and his numbers on the season are pretty remarkable, especially when you remember he didn’t even make the team out of spring training. The long-haired 25-year-old is hitting .352 with a .411 on-base percentage and .487 slugging clip, and if he had enough plate appearances he would lead the entire majors in batting average. It was already pretty well known that Dipoto had pulled off a heist in getting Segura and Haniger (and reliever Zac Curtis) from Arizona for Taijuan Walker and Ketel Marte in a trade over the offseason, but more under the radar was the move he made to get Gamel from the Yankees late last season. For the price of a pair of minor-league pitchers, the Mariners received a talented young player who is contributing now and just may keep on doing it with patience at the plate, a sweet swing when he gets the pitch he wants to hit, and an ability to swipe a bag or two and run down balls in Safeco Field’s spacious outfield.

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3. A new-look rotation.

It was just seven days ago that I was writing that the Mariners badly needed the returns of their veteran pitchers to solidify a patchwork rotation on the verge of breaking down. Well, the offense certainly helped in the interim, and while Felix Hernandez is back from the disabled list to start Friday night, he won’t be joined by Hisashi Iwakuma any time soon. The Mariners had an answer for that, though, in rookie Andrew Moore. The Mariners found the right spot for the 23-year-old out of Oregon State to make his debut, and he responded Thursday by holding a dangerous Detroit lineup to three runs on six hits and no walks – pretty much as he has been advertised – to earn his first career MLB win. Though Moore was optioned back to Tacoma to make room for Felix on Friday, he is essentially still in the rotation as Servais indicated Moore is likely to return when Seattle actually needs a fifth starter again. That won’t be for at least the next week with a pair of off days coming up. Sam Gaviglio, like Moore a rookie from Oregon State, remains in the rotation after going at least five innings and allowing fewer than two runs in four of his eight starts with the Mariners, winning out over Christian Bergman (optioned to Triple-A) and Yovani Gallardo (moved to the bullpen). That makes a rotation of Hernandez, James Paxton, Ariel Miranda, Moore and Gaviglio, which is considerably different from what the team planned out of spring training but definitely promising considering one has a Cy Young Award and the rest are all under 29 and pitching like they belong in the majors.