So, we're well past the halfway mark now as far as the 2016 season is concerned, and two of the baseball calendar's best events have come and gone this summer: the Hall of Fame Induction Ceremony and the non-waiver trading deadline. 

Which of course got me to thinking that I should compile a list of Hall-of-Famers who were moved during the season, and then made an impactful and significant effect on their team's history or playoff drive. So as always, let's take a stroll down memory lane and see some of baseball's best players change uniforms mid-season and make an impact.

1. Randy Johnson (1998) - I personally have a soft spot for the year 1998. Pokemon Red & Blue and The Legend of Zelda: Ocarina of Time were released for your Game Boys and your N64s respectively, Harry Potter and the Sorcerer's Stone hit the shelves in your local libraries and bookstores, Mulan graced the big screen, and the Titanic soundtrack (composed by James Horner) was the best-selling album of the year. Oh. And the entire nation was captivated by Mark McGwire and Sammy Sosa bringing baseball back from the dead as they spent the summer chasing down Roger Maris's home run record.  Let's face it, 1998 was one of the best years ever. And! Two future Hall-of-Famers changed teams that season making the 1998 pennant chase all the more exciting. First I'll talk about probably the lesser-remembered one, and that's Randy Johnson going from the Seattle Mariners to the Houston Astros. "The Big Unit", in his walk year, was upset that the Mariners would not grant him a contract extension allowing him to stay past the '98 campaign. Johnson's irritation showed through his work on the mound, as he only compiled a mediocre 4.33 ERA through his 23 starts with the M's in '98, far from the dominance he'd shown in the past. As a result, Seattle dealt their disgruntled ace to the Astros on Deadline Day, and a rejuvenated Johnson showed up. In 11 starts with Houston, he won 10 games, averaged 12.4 strikeouts over 9 innings, and posted a miniscule 1.28 ERA. He helped catapult Houston to the Senior Circuit's second-best record, and made them downright scary to face in the playoffs. Sadly for Johnson's Astros, they'd get knocked out in the first round by the eventual pennant-winning San Diego Padres, 3 games to 1. Johnson lost both of his starts in that series, though he didn't pitch badly (1.93 ERA over 14 innings of work = blame it on lifeless offense). Johnson's massively successful tenure in Space City allowed him to cash in during that winter's free agency. He signed a contract with the second-year Arizona Diamondbacks franchise, where he'd perform many historic feats en route to his Cooperstown enshrinement (with an Arizona 'A' on the his plaque). 

2. Mike Piazza (1998) - The second player in our mini '1998 series' over here, is one of Cooperstown's newest Hall of Famers, Mike Piazza. I had a great weekend last month watching him take his place in the Hall of Fame, and am grateful to the Mets for bringing him aboard. Before acquiring Piazza, the 1998 Mets (record of 24-20) were frequently described as a "nice little team with potential". But after? The Mets went 64-54 and were a legitimate threat in the National League. Despite the shot in the arm, the Mets fell just a tad bit short in 1998, primarily thanks to going 0-5 over the season's final 5 games, as well as a brutal call on a sacrifice fly the day before the All-Star Break. They finished 1998 just one solitary game behind the Wild Card-leading Chicago Cubs and San Francisco Giants, who had to play a tiebreaker game as a result. Could you imagine if they'd won just one of those 5 games to create a 3-way tie? The city would have been in an absolute frenzy. Partially thanks to the success and fun Piazza experienced in New York during his brief stay in Flushing during 1998, he ended up signing a long-term pact with the Mets that winter. And of course, the rest is history. Mike became one of the most beloved figures in the franchise's history, and is now the second player to don a Mets hat in the Hall of Fame.

3. Rickey Henderson (1989) -  All right, let's step away from 1998 now, and talk a little bit about the Man of Steal! Rickey Henderson  truly had an unbelievable career in baseball, where he became the game's all-time leader in stolen bases, runs scored, and at the time of his retirement, walks (since broken by Barry Bonds). And a long career he had at that. He's one of 29 players to play ball in parts of 4 separate decades, debuting as a 20-year old in 1979 with the Oakland Athletics, and hanging on until 2003, when he played for the Los Angeles Dodgers, just three months shy of his 45th birthday. Of course it's Oakland where Rickey made most of his bones, the city where he spent parts of 14 (!) seasons. He had 4 separate stints in green and gold, but it's the second stint in particular I'd like to talk about today. In the winter of 1984, Henderson was dealt to the New York Yankees in a 7-player deal. Let's now flash forward to Oakland, 1989. The A's were in a dogfight for the AL West with the Kansas City Royals. Their primary leftfielder through the middle of June had been Luis Polonia, who wasn't without his usefulness, but certainly no one's first option when it came time to name an everyday outfielder. So on June 21, 1989, the A's swung a deal with the Yankees to reacquire the star player. And the rest was history. Henderson provided far superior production out of the leadoff spot than Polonia did, and the A's eventually pulled away from the Royals in the race for the West, clinching the division with a 99-win campaign. Henderson posted a .294/.425/.438 slash over his 85 games as an A in 1989, and absolutely crushed it in the postseason. He won 1989 ALCS MVP honors and hit an absolutely ridiculous .441/.568/.941 between that series and the World Series (with 3 home runs and 11 stolen bases to boot!!). After the A's swept their cross-town rival San Francisco Giants in what is now best known as the "Earthquake Series", Henderson received the first of 2 World Series rings he'd earn in his career. Simply an astonishing trade!

4. Lou Brock (1964) -  Ever hear the term "Brock-for-Broglio"? You can Wikipedia it, it's definitely acceptable. It's used in baseball when a trade goes down, and it's quite evident that one team has unequivocally fleeced the other team to the point where the trade is laughably lopsided. And that's exactly what happened when Hall-of-Famer Lou Brock changed teams at the trade deadline in 1964. Brock originally came up with the Chicago Cubs in 1961 for a cup of coffee. His time on the Cubs was largely forgettable, posting just a .689 OPS over 1,300+ plate appearances. Once he got to the St. Louis Cardinals, his fortunes completely changed. And for that matter, so did St. Louis's.  St. Louis found themselves in 8th place, 6.5 games out in the race for the pennant. Once Brock came aboard, the Cardinals went 65-39 the rest of the way, en route to winning the NL flag, and also the 1964 World Series against the Yankees in an exciting 7-game affair. Brock's success did not end there. He'd go on to make 6 All-Star teams, win the NL stolen base crown on 8 occasions, and also hit .414 with 7 steals in the 1967 World Series, as he won his second and final World Championship when the Cards took down Dick Williams's "Impossible Dream" Red Sox in 7 games. So, what of the Cubs end of the deal? It was a 3-player package highlighted by pitcher Ernie Broglio. He went 7-19 with a 5.40 ERA with Chicago over 3 seasons of action. After 1966, his Cubs career was over, and in 1968 he was out of baseball entirely, while Brock went on to a Hall of Fame career in St. Louis. So, "Brock-for-Broglio". It's arguably the most one-sided trade in the history of baseball!

5. Tom Seaver (1977) - And last but not least, we have the infamous "Midnight Massacre" trade! One of the saddest days in New York Mets history, we need to travel back in time nearly 40 years to get there. After their improbable run to the 7th game of the World Series in 1973, the Mets followed up that memorable season by finishing in 5th place, than 3rd twice from 1974-1976. "The Franchise" Tom Seaver, the beloved, longtime righthanded ace of the club had had enough, and during spring training 1977,  he decided to speak up. He marched right up to Mets owner-at-the-time M. Donald Grant and berated him for his thriftiness when it came to spending money in order to improve the team. As a result, Grant utilized Dick Young , a Daily News columnist, to slander Seaver in the papers. Bringing his wife's name, Nancy Seaver, into the squabble, Young wrote that Seaver and his wife were jealous of Nolan Ryan (a former Met and then-California Angel) and his wife, since the Ryans were making more money over there than the Seavers were in New York. That column was where Seaver drew the line, and he demanded that Mets public relations director Arthur Richman find a new home for him. That home wound up being the Cincinnati Reds, who acquired him from the Mets on June 15, 1977 for 4 pretty good players, but nobody on the level as Tom Seaver. It began a black hole period for the Mets, who saw their attendance drop drastically. It took them 7 years to recover. As for the Seaver with the Reds, he spent 5 and a half seasons there, posting 75 wins over his 158 starts with the club. He finished second, third, and fourth in the Cy Young Award voting during 3 of those seasons, and earned a spot on 3 All-Star teams.

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