You might have seen Jose Altuve go on one of the all-time home run streaks earlier this week.

In a huge divisional matchup against the Rangers, Altuve homered in four consecutive plate appearances across two games. According to Elias, he became the first player in the expansion era (since 1961) to homer in four straight innings that his team played. It was the hottest stretch of the career of one of baseball's best players of the last decade.

Altuve's incredible home run barrage continued a trend for a player who has turned the clock back to his MVP days. Altuve posted a career-best 164 wRC+ last season and has followed it up with a 162 wRC+ this season, blowing way past his career 130 wRC+ and even besting the 160 figure he had in his 2017 MVP season. This comes after he seemingly settled in at a new level from 2018-2021 (127 wRC+). 

Altuve, who has spent time on the injured list twice this year, has been even better since returning on July 26. His 2.6 fWAR and 184 wRC+ are both top-five figures in the Majors during that time.

Here's what's changed for the 33-year-old and how Altuve reverting back to his peak years has the Astros looking for their seventh straight playoff appearance.

All numbers are through Friday's games

Becoming more of a three true outcomes hitter

When Altuve first came to the Majors, his profile mirrored that of your classic throwback hitter: lots of hits and contact and few walks and home runs. The 2023 version of Altuve is almost unrecognizable from the player who debuted in 2011.

As the game has shifted to more three true outcomes -- home runs, strikeouts and walks -- so too has Altuve. And then some.

Altuve's three true outcomes% vs. league average

2011-15 seasons: 16.7 TTO% vs. 30.2%
2016-21 seasons: 25.5 TTO% vs. 34.1%
2022-23 seasons: 31.4 TTO% vs. 33.9%

Altuve will hardly be confused with the Gallos and Schwarbers of the baseball world but his profile has shifted in a drastic way. Compared to his first five seasons, the percentage of Altuve's plate appearances resulting in a home run, walk or strikeout has nearly doubled in the last two seasons.

Altuve's PA/HR rate, walk rate and strikeout rate

2011-15 seasons: 81.4 PA/HR // 5.0 BB% // 10.5 K%
2016-21 seasons: 26.7 PA/HR // 8.7 BB% // 13.0 K%
2022-23 seasons: 21.4 PA/HR // 11.2 BB% // 15.5 K%

This season, Altuve is walking at a career-high rate (11.7%) and striking out more than ever (17.6%). His 21.1 PA/HR rate is second only to his 2019 season (17.7), a year when MLB set a single-season home run record. The approach looks to be intentional.

Altuve is swinging less than ever over the last two seasons (44.4%) and is offering at first pitches a career-low 37.2% of the time in 2023. That selectivity has led to a career-low 61% first-pitch strike rate against him, which has led to massive results for Altuve. When he gets ahead in the count, Altuve is hitting .550/.703/1.250 in 64 plate appearances with a 1.953 OPS that is tops in the Majors.

When Altuve debuted in 2011, he profiled perfectly as a leadoff hitter with tons of hits and speed. As the game has evolved, and teams have implemented new approaches to lineup strategy, Altuve remains a great leadoff hitter despite the changes in his profile.

Mashing fastballs

Opposing pitchers might want to think twice about throwing any fastballs to Altuve.

He's always handled fastballs quite well -- he posted a .317/.374/.492 line against fastballs in his first 11 MLB seasons -- but he's hitting them better than ever in the last two seasons.

Highest OPS against fastballs, since 2022
Min. 500 PA ending on fastballs

1. Aaron Judge (NYY): 1.194
2. Shohei Ohtani (LAA): 1.089
3. Jose Altuve (HOU): 1.079
4. Lars Nootbaar (STL): 1.019
5. Mookie Betts (LAD): .996

Altuve is having a career-best year against fastballs in 2023. After crushing those pitches to the tune of a 1.029 OPS last season, that number has jumped to 1.168 this season, which only trails Judge and Ohtani. It doesn't matter what kind of fastball it is. If it's a four-seamer, two-seamer or cutter, Altuve is going to do damage against it.

Altuve's OPS and HR against fastball types, since 2022

Four-seamers: 1.137 OPS, 22 HR
Two-seamers: .974 OPS, 6 HR
Cutters: .972 OPS, 6 HR

Surprisingly, the fastball usage hasn't budged much against Altuve despite these numbers. 52.8% of the pitches he's seen the last two seasons have been fastballs, just below the league-average mark of 55.7%. Pitchers are throwing even more fastballs (up about 2%) to him this year and that hasn't changed much as the year has progressed.

Pitchers could benefit from throwing Altuve fewer fastballs. In 2022, Altuve's .794 OPS against non-fastballs was comfortably above the league-average mark of .626. This year, however, Altuve's OPS against breaking balls and offspeed pitches has dropped to .677, which is just above the .655 league-wide OPS.

Whereas hitters like Ohtani, Judge and Betts crush non-fastballs, Altuve has been merely human against them. It'll be interesting to see if the approach changes against Altuve for the remainder of the season and heading into the playoffs -- assuming the Astros once again find themselves there.

Can Altuve sustain this level?

Given his career trajectory, you'd be hard-pressed to doubt what Altuve can do but there are at least a few indicators that he might be overperforming a bit this season.

Among hitters with at least 300 plate appearances in 2023, Altuve has a top-30 BABIP (.350), the highest it's been since 2018. Altuve used to consistently run high BABIPs when he was one of the league's quickest players. With injuries and age, Altuve's average sprint speed is now in the 28th percentile in 2023 -- making it a lot more difficult to sustain that kind of BABIP.

Altuve's home run/fly-ball rate (21.4%) ranks in the top 40 and is the second-highest of any season in his career behind only his 2019 season. If you're thinking that's due to the short porch at Minute Maid Park, think again. Of his 15 home runs this season, a dozen have come on the road.

Most notably, Altuve's .406 wOBA is a whopping 55 points above his .351 expected wOBA -- based on the quality of contact (exit velocity, launch angle), strikeouts and walks. Only two hitters have a larger positive difference between those two numbers this season. The 61-point gap between his .315 BA and .254 expected BA is the largest in the Majors.

That said, Altuve has shown an ability to play above his underlying numbers for most of his career. Among hitters with at least 2,000 plate appearances in the Statcast era (since 2015), only three hitters have outperformed their expected OBA more than Altuve (29 points). For great players like Altuve -- who has also been somewhat of an anomaly given his profile -- he's probably deserved the benefit of the doubt.

As the Astros inch closer to yet another playoff appearance and try to defend their 2022 title, it's their longest-tenured player who is playing as well as ever before. If he keeps this up, the Astros might just repeat as World Series champs.