South Korean footballers in Europe have wrapped up their seasons with regrets, as most of them failed to make strong impressions on their fans and coaches alike.

The major European football leagues completed their 2015-16 campaigns over the weekend, and South Korean footballers in the English Premier League and the German Bundesliga closed their seasons with a mixed bag of performances.

Koo Ja-cheol of FC Augsburg enjoyed the most impressive performance. The 27-year-old midfielder, who joined Augsburg from Mainz last August, scored a career-high eight goals in 27 matches. He had seven goals last season -- five in the league and two in cup competitions -- with Mainz.

Though he picked up a toe injury on May 7 against Schalke 04, Koo played 2,079 minutes in the Bundesliga this season, 593 minutes more than last season. With his first career hat trick against Bayer Leverkusen in March, Koo has solidified his status in Augsburg as a core member.

Koo's teammate Hong Jeong-ho also had a promising season, as the defender earned more playing time on the pitch. Hong, who joined Augsburg in 2013, suffered an ankle injury in late October and was forced to miss 40 days. However, he gradually improved his form and bagged two goals for the season.

The 26-year-old played 1,714 minutes in 23 matches in 2015-2016, six matches and 776 minutes more than the previous season.

However, Ji Dong-won, another South Korean on Augsburg, had a season he'd rather forget, with zero goals in 21 matches. The 24-year-old forward only played 781 minutes this season, usually as a second-half substitute.

But Ji's situation was at least better than that of Kim Jin-su of Hoffenheim and Park Joo-ho of Borussia Dortmund, also in the Bundesliga. The two South Korean left backs had good starts to the season, but they failed to become regulars and warmed the bench for much of the season. Some pundits now expect that they could leave their current clubs.

Kim ended up playing only 15 matches, four fewer than the previous season. The 23-year-old was once thought to be a mainstay, but after the 28-year-old coach Julian Nagelsmann took over the team in February, Kim wasn't featured in Bundesliga matches. His last appearance dates back to Feb. 1, when Hoffenheim faced Bayern Munich.

Park's situation was no different. After moving to the Bundesliga powerhouse Borussia Dortmund from Mainz last August, the 29-year-old had a solid debut, scoring a goal and an assist against Krasnodar in the UEFA Europa League in September. But since then, he has been struggling to get off the bench as German international Marcel Schmelzer kept playing well as the left back.

Park's last appearance with Dortmund was on Jan. 23 against Borussia Monchengladbach. He completed the season with five Bundesliga matches and four UEFA Europa League matches under his belt. Last season with Mainz, Park played 16 matches in the Bundesliga alone.

In England, Son Heung-min found himself under the spotlight after joining Tottenham Hotspur from Bayer Leverkusen, reportedly with a record transfer fee for an Asian footballer. He only had a modest first season in the EPL.

Son had four goals and an assist in the league, while notching three goals and four assists in the Europa League. He also scored a goal at the English Football Association Cup against league champions Leicester City in January.

The 23-year-old forward had ups and downs throughout the season. Son had a quick start to his Tottenham career, collecting two goals against Azerbaijan's Qarabag in the Europa League and the winner against Crystal Palace in the EPL in September. But after suffering a foot injury against Manchester City on Sept. 26, he was sidelined for six weeks and lost playing time to the likes of Erik Lamela and Dele Alli.

Son, however, scored in back-to-back league matches in his late push.

In his EPL debut season, Son played 1,104 minutes total in 28 matches, compared with 2,291 minutes in 30 matches last season with Bayer Leverkusen. He played under 10 minutes in seven of those 28 EPL contests.

It was a tough season for Swansea City midfielder Ki Sung-yueng, who went from an integral member of the club to a spare part while dealing with assorted injuries.

Ki, 27, last season notched eight goals in the EPL, the most among Asian footballers in a single season, but he only managed to bag two goals and an assist this time. Also, he only played 1,851 minutes in 28 matches this season, after logging 2,690 minutes in 33 contests the previous season.

With midfielders like Jack Cork, Leon Britton and Leroy Fer getting more playing time, Ki fell out of favor with coach Francesco Guidolin, who got the job in January. As the Italian manager signed a contract extension with the Welsh club, some English media are now speculating that Ki might leave Swansea this summer.

Lee Chung-yong of Crystal Palace had a troubled season both on and off the pitch.

Lee's best performance came on Dec. 19 last year, when he scored the late winner in a 2-1 victory over Stoke City. However, he remained silent for most of the season, playing only 385 minutes in 13 matches for the London club.

What makes Lee's future doubtful at the Palace is his relationship with manager Alan Pardew. He was recently fined by the club after criticizing Pardew in an interview with South Korean media, saying the manager is running the club with "a very short-term vision." The former Bolton Wanderers player even said, "There is no reason to stay at this club," hinting that he will find a new club for next season.

Meanwhile in Portugal, striker Suk Hyun-jun made headlines after moving from Vitoria Setubal to two-time UEFA Champions League winners FC Porto in January. But he also failed to impress and was given less playing time with Porto than he had with Vitoria. The 24-year-old scored nine goals in 16 matches with Vitoria in the first half of the season, but just one goal in nine matches with Porto. (Yonhap)